Bibcode

The bibcode is an identifier used by a number of astronomical data systems to specify literature references. The bibcode was developed to be used in SIMBAD and the NASA/IPAC Extragalactic Database (NED), but is now used more widely, for example, in the NASA Astrophysics Data System. The code has a fixed length of 19 characters and has the form YYYYJJJJJVVVVMPPPPA , where YYYY is the four-digit year of the reference and JJJJJ is a code indicating where the reference was published. In the case of a journal reference, VVVV is the volume number, M indicates the section of the journal where the reference was published (e.g., L for a letters section), PPPP gives the starting page number, and A is the first letter of the last name of the first author. Periods (.) are used to fill unused fields and to pad fields out to their fixed length if too short; padding is done on the right for the publication code and on the left for the volume number and page number. Some examples of the code are as follows: