The bibcode syntax is: yyyyjjjjjvvvvlppppa where:
		* yyyy: Year of publication
		* jjjjj: A standard abbreviation for the journal. A list of
                  abbreviations is available at
                  http://adsabs.harvard.edu/abs_doc/journal_abbr.html
		* vvvv: The volume number (for a journal) or an abbreviation
                  that specifies what type of publication it is (e.g. conf for
                  conference proceedings, meet for Meeting proceedings, book
                  for a book, cong for congress proceedings). Volume numbers
                  are left padded with periods.
		* m: Qualifier for publication: L for Letter, P for Pink page,
                  Q-Z: Unduplicating character for identical codes
		* pppp: Page number.  Page numbers are left padded with
                  periods.
		* a: The first letter of the last name of the first author.

bibcode identifiers are case-sensitive.  For the jjjjj part of the identifier,
the case provides some information: all letters are lower case for conferences,
while for journals the first letter is always upper case and the other letters
are mixed case.  For the l part of the identifier (14th position), the case
also provides some information, even though it does not distinguish between
different bibcodes.  Lower case letters are used for issue numbering, while
uppercase letters are used for unduplicating bibcodes and for Letters pages.