Article 29

• Publication is effected, under this Code, by distribution of printed matter (through sale, exchange, or gift) to the general public or at least to scientific institutions with generally accessible libraries. Publication is also effected by distribution on or after 1 January 2012 of electronic material in Portable Document Format (PDF; see also Art. 29.3 and Rec. 29A.1) in an online publication with an International Standard Serial Number (ISSN) or an International Standard Book Number (ISBN).
  • The paper containing the new combination Anaeromyces polycephalus (Y. C. Chen & al.) Fliegerová & al. (Kirk in Index Fungorum 1: 1. 2012), based on Piromyces polycephalus Y. C. Chen & al. (2002), was effectively published when it was issued online in Portable Document Format with an ISSN on 1 January 2012.
  • The distribution before 1 January 2012 of electronic material does not constitute effective publication.
  • Floristic accounts of the Asteraceae in Flora of China 20–21, containing numerous nomenclatural novelties, were published online in Portable Document Format on 25 October 2011. Because they were distributed before 1 January 2012 and lacked either an ISBN or an ISSN they were not effectively published. Effective publication occurred when the printed version of the same volume became available on 11 November 2011.
  • The paper in which the diatom Tursiocola podocnemicola was first described was distributed online on 14 December 2011 as an “iFirst” PDF document (DOI: 10.1080/0269249X.2011.642498) available through the Diatom Research website (ISSN 0269-249X, print; ISSN 2159-8347, online). Although the paper appeared online in an ISSN-bearing electronic publication in Portable Document Format, it was distributed before 1 January 2012 and was not therefore effectively published. It did not become effectively published on 1 January 2012 merely by remaining available online. Effective publication occurred on 28 February 2012, when the printed version of the journal (Diatom Res. 27: 2. 2012) was distributed.
• For the purpose of Art. 29.1, “online” is defined as accessible electronically via the World Wide Web.
• Should Portable Document Format (PDF) be succeeded, a successor international standard format communicated by the General Committee (see Div. III) is acceptable.

Recommendation 29A

• Publication electronically in Portable Document Format (PDF) should comply with the PDF/A archival standard (ISO 19005).
• Authors of electronic material should give preference to publications that are archived and curated, satisfying the following criteria as far as is practical (see also Rec. 29A.1):
  • The material should be placed in multiple trusted online digital repositories, e.g. an ISO-certified repository.
  • Digital repositories should be in more than one area of the world and preferably on different continents.
  • Deposition of printed copies in libraries in more than one area of the world and preferably on different continents is also advisable (but see Rec. 30A.2).