Nexus Standards · NS-2 · Proposed
NS-2
NS-2: Citation and attribution format for UNIs
NS-2 is a proposed Nexus Standard; the artifacts it governs are identified by UNIs (Unique Nexus Identifier). NS-2 specifies how people and machines cite an artifact or record identified by a UNI, so that attribution is exact, versioned and resolvable, and so that the publisher of record receives credit. The publisher of record is an institution; the owner of a technology is not the publisher by default.
Summary
- Statusproposed
- Responsible scopetrust, authorization and assurance; knowledge, records and learning
- Identifier
NXS-STD-ST-000009 - Rules stated5
- Programme areas2
- Source filesrepository
Nexus Standards · proposed
Status of NS-2
Preparatory working draft, circulated for review and comment. Not for implementation. Prepared and circulated by The Secretariat of the Nexus Standards, Global Centre for Risk and Innovation (GCRI Canada) (public@therisk.global), 17 October 2026. Technical review area: TR-03. This document is not a Nexus Standard; it may change without notice and is not to be implemented, relied upon or cited as a Nexus Standard. Its stage is designated only by the Global Standards Council and its technical committees under NS-13. Recipients are invited to submit comments with supporting reasons, and to notify any patent rights of which they are aware. See the notice of circulation.
Electrified and connected activity in Europe
The map frames Europe as an example geography for the subject of NS-2; the frame gives context and is not a statement of where the standards apply. Shown at first: night-time lights, daily (VIIRS Black Marble, VNP46A2, NASA LAADS DAAC) and population density, 2020 (Gridded Population of the World v4.11, NASA SEDAC, CIESIN, Columbia University). The layer drawer adds true colour (VIIRS NOAA-20 corrected reflectance). NASA products are served through NASA GIBS under NASA's open data policy, with acknowledgement; population density is GPW v4.11 by CIESIN, Columbia University, under CC BY 4.0; coastlines, boundaries and place names come from NASA GIBS reference layers (© OpenStreetMap contributors, ODbL) and Natural Earth (public domain). Each layer shows its own observation date; full credits are given under the map.
The interactive map needs JavaScript; the layer list and sources are below.
Layers 2
Connected activity
Keyboard, with the map focused
Hold Ctrl or ⌘ and scroll to zoom
Latest available
NASA GIBS / EOSDIS · ASTER GDEM (METI, NASA) · Blue Marble (NASA) · © OpenStreetMap contributors (ODbL) · Natural Earth
Loading the latest NASA imagery.
Drag to move. Ctrl or ⌘ and scroll, pinch or the buttons to zoom; hover for the values under the pointer; reset returns to the region.
Night-time lights and population density, the footprint of electrified, connected activity, framed on Europe.Satellite and model products as NASA publishes them, each with its own date; indicators, not assessments of any place.
Data: NASA GIBS · ASTER GDEM · Blue Marble · © OpenStreetMap contributors · Natural EarthSources and licences
- We acknowledge the use of imagery provided by services from NASA's Global Imagery Browse Services (GIBS), part of NASA's Earth Science Data and Information System (ESDIS). Colours redrawn from the published colour map; values averaged into H3 cells where shown (modified). NASA open data
- We acknowledge the use of imagery provided by services from NASA's Global Imagery Browse Services (GIBS), part of NASA's Earth Science Data and Information System (ESDIS). Colours redrawn from the published colour map; values averaged into H3 cells where shown (modified). NASA open data
- VIIRS Black Marble night-time lights, NASA Goddard Space Flight Center; distributed by the NASA Level-1 and Atmosphere Archive and Distribution System (LAADS DAAC); imagery via NASA GIBS. Colours redrawn from the published colour map; values averaged into H3 cells where shown (modified). NASA open data
- Center for International Earth Science Information Network (CIESIN), Columbia University. 2018. Gridded Population of the World, Version 4 (GPWv4): Population Density, Revision 11. NASA Socioeconomic Data and Applications Center (SEDAC). Licensed under CC BY 4.0. Colours redrawn from the published colour map; values averaged into H3 cells where shown (modified). doi:10.7927/H49C6VHW. CC BY 4.0
- VIIRS near-real-time products (flood, land surface temperature, snow cover, corrected reflectance), NASA LANCE; imagery via NASA GIBS. Colours redrawn from the published colour map; values averaged into H3 cells where shown (modified). NASA open data
- ASTER GDEM is a product of METI and NASA (ASTER Global Digital Elevation Model V003, NASA LP DAAC); imagery via NASA GIBS. Colours redrawn from the published colour map; values averaged into H3 cells where shown (modified). Cite as: NASA/METI/AIST/Japan Spacesystems and U.S./Japan ASTER Science Team (2019). ASTER Global Digital Elevation Model V003. doi:10.5067/ASTER/ASTGTM.003. NASA open data
- Made with Natural Earth. Free vector and raster map data @ naturalearthdata.com. Public domain
- © OpenStreetMap contributors (ODbL), via NASA GIBS (coastlines, boundaries, roads and place names). Colours redrawn from the published colour map; values averaged into H3 cells where shown (modified). ODbL
- Blue Marble, NASA Earth Observatory; imagery via NASA GIBS. Colours redrawn from the published colour map; values averaged into H3 cells where shown (modified). NASA open data
- Context on the globe and flat map: coastlines, boundaries, roads and place names from NASA GIBS reference layers (OpenStreetMap data, ODbL, © OpenStreetMap contributors); Blue Marble imagery as an optional base; 3D terrain and the elevation read-out from the ASTER GDEM elevation colour index (5 m to 200 m classes, exaggerated for legibility). Boundaries are drawn as published and imply no position on any territory.
- Globe: MapLibre GL JS 6.9.1, BSD-3-Clause, © MapLibre contributors.
- NASA GIBS: We acknowledge the use of imagery provided by services from NASA's Global Imagery Browse Services (GIBS), part of NASA's Earth Science Data and Information System (ESDIS).
- Optional layers (3 sources in the layer list: live, forecast, observed and context) print their provider credit on the map and here when switched on; forecasts are model output and derived indices are estimates.
Layers and dates
- Night-time lights, daily: VIIRS Black Marble (VNP46A2), NASA LAADS DAAC · 12 Oct 2026
- Population density, 2020: Population: CIESIN, Columbia University, Gridded Population of the World v4.11 (2018), NASA SEDAC, CC BY 4.0 · static
- True colour: VIIRS NOAA-20 corrected reflectance, NASA LANCE · 13 Oct 2026
NS-2 among the standards.
Fig.The standards on which NS-2 builds, those that cite it and the programme areas where it applies, from the texts and the registry.
The standard as a process
A citation starts from the record of what is cited, takes one of four forms, cites a version where a state is meant, credits creators and the publisher of record, cites every source of a derived work and resolves through the resolver or a DOI. 7 operations in 5 phases; each states its actor, its decision rule, the record it leaves and the rule identifiers it implements (5 rules of NS-2 and the standards it applies). Records and artifacts are cited by UNI (Unique Nexus Identifier) and version.
All operations in order (7)
- 01
Cited record start · Cited record
Creators and publisher are read from the record of the artifact or the data record being cited, never retyped.
- Who
- the publisher of record
- Decision rule
- attribution follows the record
- Record
- the catalog record with creators, publisher and version
- Implements
- NS2-R3
- 02
Choose the form decision · Form
Each form carries the UNI; a DOI, where one exists, follows the UNI and never takes its place.
- Who
- the citing author or system
- Decision rule
- short form for captions and interfaces, full form for reference lists, record form for data, URN for machines (section 1)
- Record
- the short, full, record or machine form
- Implements
- NS2-R1
- 03
Concept or version gate · Form
A citation without a version cites the concept; a claim about a state of the artifact cites the version that holds it.
- Who
- the citing author
- Decision rule
- versioned claims cite a version; concept citations are explicit
- Record
- UNI@version, or an explicit concept citation
- Implements
- NS2-R2
- 04
Credit creators step · Attribution
Institutions remain publisher of record; an agent that produced an artifact is credited as an agent.
- Who
- the citing author
- Decision rule
- the publisher of record is credited; agents are credited as agents with their mandate
- Record
- creators and publisher of record named
- Implements
- NS2-R3
- 05
Cite the sources step · Attribution
A figure cites the datasets it draws; a report cites the records behind its numbers, through the derivation relations of NS-3b.
- Who
- the author of the derived work
- Decision rule
- derived works cite their sources' UNIs; an omitted source is a provenance defect
- Record
- a reference to every source UNI
- Implements
- NS2-R4
- 06
Citation record · Citation
The citation is complete when a reader or a machine can reach the exact record from it.
- Who
- the citing author
- Decision rule
- every citation carries its UNI; a name alone never cites
- Record
- the citation with UNI, version where needed, title, publisher and link
- Implements
- NS2-R1
- 07
Resolve end · Resolution
A citation that does not resolve is a defect to be corrected, not a style choice.
- Who
- the resolver (NS-7) or the DOI system
- Decision rule
- every cited UNI resolves through the resolver or a DOI
- Record
- the record reached from the citation
- Implements
- NS2-R5
Fig.Phases read left to right; each card names the operation, its actor and the record it leaves, and each edge label names the hand-over. Play, step or scrub; the detail panel gives the full text of the selected operation. Sources: NS-2: Citation and attribution format for UNIs.
NS-2 clause by clause
3 clauses and 5 rules as stated in the standard, presented with numbered clauses, stable rule anchors, versions and changes.
Forms
| Form | Pattern | Example |
|---|---|---|
| Short (inline, captions, user interfaces) | UNI or UNI@version | NXS-GRX-RP-M002-000007@1.2.0 |
| Full (reference lists) | Creators (Year). Title (Version). Publisher. UNI. DOI-or-URL. | GCRI Canada (2026). Africa flood exposure 2026 (1.2.0). GCRI Canada. NXS-GRX-RP-M002-000007@1.2.0. https://nexustandards.com/uni/NXS-GRX-RP-M002-000007 |
| Record | recordUni@recordVersion with the source release | NXS-GRX-OB-KEN-000042@3 (release NXS-GRX-SR-000001) |
| Machine | URN urn:nexus:uni:<uni>; CITATION.cff (Citation File Format 1.2.0) and DataCite exports (NS-1 section 8) |
A citation without a version cites the concept; a citation with a version cites one state. Where a DOI exists it is given after the UNI; the UNI is never omitted. The full form is a pattern of elements, not a typographic style: an implementation may render it in any citation style or language, provided that every element is present.
Attribution
Creators and publisher are taken from the record (creators, publisherRef). An agent that produced an artifact is credited as a creator of type Agent, with its mandate; the responsible institution remains publisher of record. A derived work cites every IsDerivedFrom and Compiles relation of its record (NS-3b, PROV-O); a figure cites the datasets and records it draws (NS-5).
Rules
| Rule | Text |
|---|---|
| NS2-R1 | Every citation of an artifact or record identified by a UNI shall carry its UNI; a name alone does not cite. |
| NS2-R2 | A claim about one version shall cite that version; a citation of the concept shall be explicit. |
| NS2-R3 | Attribution shall follow the record: the publisher of record is credited, and agents are credited as agents. |
| NS2-R4 | A derived work shall cite the UNIs of its sources; the omission of a source is a provenance defect, not a matter of style. |
| NS2-R5 | Citations shall resolve: the resolver (NS-7) or a DOI shall answer for every cited UNI. |
Changes between versions
One published version is available (0.1.0); a comparison between versions is shown once a second version is published.
Clause numbers follow the sections of the document; rule identifiers (NS2-R1, NS2-R2, NS2-R3…) are stable anchors. With script enabled, each clause and rule has a permalink and a machine-readable view (YAML and JSON), and the j and k keys move between clauses.
Programme areas that list NS-2
2 programme areas list NS-2.
Recent research on NS-2
Recent peer-reviewed articles, preprints, datasets and reports on the subject of this standard, retrieved at the time of reading from open scholarly metadata services (OpenAlex, Crossref, DataCite, Zenodo, arXiv, Europe PMC, OpenAIRE Graph) with search terms composed from the registry. Each work is listed with its authors, venue, year, type, open-access status and licence, and links to its DOI or landing page. Sources not yet enabled for live display on this site are listed for reference and are not queried.
Search termsdata citation; software citation; dataset citation; citation of data; DataCite Metadata Schema; in-toto Attestation Frameworkcombined with: research; data; software; metadataDerived from the subject of the standard and its rules, and the external standards of its crosswalk domains.
- OpenAlexlisted for reference; not queried
- Crossreflisted for reference; not queried
- DataCitelisted for reference; not queried
- Zenodolisted for reference; not queried
- arXivlisted for reference; not queried
- Europe PMClisted for reference; not queried
- OpenAIRE Graphlisted for reference; not queried
No source is enabled for live display on this site yet: the sources are listed for reference and none is queried. Once the publisher of record enables a source after its terms are reviewed, recent works are listed here. Metadata and links only: title, authors, venue, year, type, open-access status and licence as each source records them; works are listed for orientation, not reviewed or endorsed.
NS-2 in the standards repository
The text, schemas, machine-readable files, registry rows, tests and history behind NS-2, on the main branch of the canonical repository. Text, registry, schemas and catalog are CC BY 4.0; tools and tests are Apache-2.0.
Source text
| File | What it holds | Links |
|---|---|---|
standards/NS-2-citation-and-attribution.md | NXS-STD-ST-000009 | Raw · History · Suggest an edit |
standards/INDEX.md | status and document of every standard | History |
Machine-readable files
| File | What it holds | Links |
|---|---|---|
catalog/artifact-catalog.yaml | catalog records · 2 mentions | First mention, line 395 |
Registry rows
| File | What it holds | Links |
|---|---|---|
registry/ecosystem-coverage.yaml | Nexus ecosystem coverage register (programme B corpus read) · 10 rows or mentions | Line 59 |
registry/standard-packages.yaml | Standard packages - one package per external open standard on nexustandards.com · 5 rows or mentions | Line 54 |
registry/dags.yaml | Process and pipeline graphs rendered by the site's DAG component (nxs-dag) · 2 rows or mentions | Line 36 |
registry/review-investigations.yaml | Circulation for technical review and comment, and the technical review areas · 2 rows or mentions | Line 68 |
registry/subsites.yaml | Nexus Standards subsites - the systemic architecture of nexustandards.com · 2 rows or mentions | Line 69 |
registry/open-standards-stack.yaml | Open-standards and open-source stack under the UNI · 1 row or mentions | Line 128 |
Tests and validators
| File | What it holds | Links |
|---|---|---|
tools/build-risk-standards.mjs | tool or validator | Line 97 |
tools/build-site-pages.mjs | tool or validator | Line 292 |
tools/validate.mjs | tool or validator | Line 150 |
Change history
| File | What it holds | Links |
|---|---|---|
| Commits to the text | every change to the text | · |
CHANGELOG.md | notable changes, by version | · |
release/manifest.json | release manifest with file digests | in-toto statement |
| Releases | tagged releases of the repository | · |
Propose a change
| File | What it holds | Links |
|---|---|---|
| Open a proposal on NS-2 | issue form: target, kind, rationale (NS-13) | Template |
| Issue form: comment | issue form | Template |
| Issue form: errata | issue form | Template |
| Issues that mention NS-2 | open and closed | · |
| Pull request template | what a change must carry: target, kind, rationale, validation | · |
CONTRIBUTING.md | pull requests, sign-off and checks | · |
GOVERNANCE.md | how registry codes and texts change | · |
How NS-2 is developed, and how to take part
NS-2 is developed in the open under NS-13 (the stages and gates of NS-13). Working groups draft, councils decide the reserved matters, and anyone may propose a change, comment, submit an implementation report, object or appeal, without membership or fee.
- Who decides what: the decision-rights matrix.
- The process: stages, gates, review windows and appeals.
- Open gateways and calls: how to propose, comment, join a working group or request activation.
- Develop a standard: the development track and the lifecycle of each standard.
- NS-13 in the canonical repository.
Relation to external standards
NS-2 relates to external standards by identifier, clause number and URL (NS14-R1), and directs the reader to the issuing body.
Recent research and sources
Peer-reviewed articles, preprints, reports and datasets on the subject of this standard, retrieved at the time of reading from open scholarly metadata services (OpenAlex and Crossref) and listed with authors, venue, year, type and access status, with a link to each work. Curated references and related standards are listed first; recent works matched by subject follow and are listed for orientation.
Curated references
- A data citation roadmap for scientific publishers
Scientific Data · 2018 · Peer-reviewed - Software citation principles
PeerJ Computer Science · 2016 · Peer-reviewed - Recognizing the value of software: a software citation guide
F1000Research · 2021 · Peer-reviewed - Crossref: The sustainable source of community-owned scholarly metadata
Quantitative Science Studies · 2020 · Peer-reviewed - Large-scale comparison of bibliographic data sources: Scopus, Web of Science, Dimensions, Crossref, and Microsoft Academic
Quantitative Science Studies · 2021 · Peer-reviewed - OpenAlex: A fully-open index of scholarly works, authors, venues, institutions, and concepts
arXiv · 2022 · Peer-reviewed - The FAIR Guiding Principles for scientific data management and stewardship
Scientific Data · 2016 · Peer-reviewed - The CARE Principles for Indigenous Data Governance
Data Science Journal · 2020 · Peer-reviewed
Related standards and frameworks
- SoftWare Hash IDentifier (SWHID) Specification V1.2; ISO/IEC 18670:2025
Software Heritage; ISO/IEC JTC 1 - W3C Verifiable Credentials Data Model v2.0
W3C Verifiable Credentials Working Group - Sigstore (Cosign, Fulcio, Rekor)
OpenSSF (Linux Foundation); graduated project March 2024 - DataCite Metadata Schema 4.5
DataCite Metadata Working Group - UN M49 Standard country or area codes for statistical use
United Nations Statistics Division - in-toto Attestation Framework
in-toto project (CNCF) - W3C Decentralized Identifiers (DIDs) v1.0
W3C DID Working Group - Research Organization Registry (ROR)
ROR (California Digital Library, Crossref, DataCite)
Search terms, derived from the subject of the standard and its rules: data citation; software citation; dataset citation; citation of data; combined with: research; data; software; metadata. With JavaScript enabled, recent works matching these terms are listed from OpenAlex and Crossref.
Risk Academy courses and disciplines
2 courses and 2 disciplines of Risk Academy (risksacademy.com) that teach the knowledge and methods of NS-2. Each course lists its level, stream and learning hours.
Courses
Disciplines
The correspondence between courses, disciplines and the Nexus Standards is maintained with Risk Academy and is subject to its academic review.
Programmes, tracks and courses for this standard
GCRI Canada and Risk Academy work on the subject of NS-2 in distinct roles (research and evidence; education and training). Each entry states why it corresponds and the step it offers; each institution sets its own terms of participation.
Research and evidence
GCRI Canada
Research programmes that produce the observations, models and assessments these records describe.
Nexus ReportsPublishes versioned and sourced reports.Apply to this programme therisk.globalAll programmes of GCRI CanadaEducation and training
Risk Academy
Courses and disciplines that teach the knowledge and methods practitioners need to apply these standards.
Science Policy 101RAF-103 · Introductory · 19.5 learning hoursBringing evidence on risk to decision makers honestly, clearly and usefullyTake this course Clausecraft and LicensingRAT-202 · Intermediate · 20 learning hoursLicences, attribution, data-sharing agreements and risk-transfer clauses for risk tools, at a methods levelTake this course All courses and disciplinesListed in the education and training section of this pageQuestions and answers.
What is the status of NS-2?
What does applying NS-2 establish?
How is a change to NS-2 proposed?
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Status and use. The Nexus Standards are proposed standards developed through an open process under NS-13 and published for voluntary use; they do not constitute certification, accreditation or regulatory approval, and adoption remains a decision of the Global Standards Council and, in each country, of its National Standards Council. A UNI (Unique Nexus Identifier) identifies an artifact; it does not certify it. Names of standards bodies and their standards belong to their stewards and are used only to identify the documents; no text of an external standard is reproduced here. Nexus Standards is not affiliated with, endorsed by or certified by any standards body named here.
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