# Background Standard identifiers are a crucial element when searching for publications. Standard identifiers include valuable details, such as the publication year, so that the customer knows which version is the latest. When searching for standard identifier 'BS EN 12542', a search engine should retrieve all available versions. The user is able to distinguish between the latest 2020 edition and the previous versions from 2010 and 2002. The standard identifier also informs the customer if a publication is a standalone publication, such as the example above, or if it is part of a series, e.g. BS ISO 18589 has multiple parts It is very rare for Standards users to use the exact title of the publication to use when performing searches. They are more inclined to use keywords or only part of the title as the full title may have changed from the last version or is simply not known to the customer. # Observed behavior The current behaviour using the Crossref search engine can be demonstrated using the example 'BS EN 12542:2020'. When searching for 'BS EN 12542:2020', the following is returned, but amongst thousands of other publications. If there are standards users performing searches on particular identifiers on Crossref website, they will not be able to locate the required publication. This is the case for all BSI standards and it prevents customers from accessing the publications of their interest via Crossref search. If you search on the title of the standard 'LPG equipment and accessories. Static welded steel cylindrical pressure vessels, serially produced for the storage of Liquefied Petroleum Gas (LPG) having a volume not greater than 13 m³. Design and manufacture', the standard appears as the first match (doi.org/10.3403/30326249). It is very rare for customers to use the exact title of the publication to use when performing searches. They are more inclined to use keywords or only part of the title as the full title may have changed from the last version or is simply not known to the customer. As there is no identifier available in the search results, the customer will be unable to successfully identify which results are related to BS publications, and they will not find the exact match for their identifier query. # Expected behavior Search on identifier is detected as a Standard identifier and the correct match shown first. When searching for standard identifier 'BS EN 12542', a search engine should retrieve all available versions. The user is able to distinguish between the latest 2020 edition and the previous versions from 2010 and 2002. [comment]: # (No need to update the Definition of ready when filing issues, but feel free to have a go if you're familiar with the territory.) # Definition of ready - [X] Product owner: @bvickery1 - [X] Tech lead: @eshadatta-crossref - [X] Service:: label applied - [ ] Definition of done updated - [ ] Acceptance testing plan: - [ ] Weight applied [comment]: # (Feel free to leave this as is, or suggest changes. We'll update these during Backlog Refinement, prior to bringing this into a sprint.) # Definition of done - [ ] Unit tests identified, implemented, and passing - [ ] Code reviewed - [ ] Available for acceptance testing via a staging URL, or otherwise - [ ] Consider any impacts to current or future architecture/infrastructure, and update specifications and documentation as needed - [ ] Knowledge base reviewed and updated - [ ] Public documentation reviewed and updated - [ ] Acceptance criteria met - [ ] AC 1 - [ ] AC 2 - [ ] Acceptance testing passed # Notes [comment]: # (By default all issues need to be labeled Planning::New, only remove if you know what you're doing)