Everyone is invited to contribute to the graph grammar bibliography, just by sending new or updated entries to Frank Drewes - drewes@cs.umu.se. The rules are as follows:

• All entries sent should comply with the standard BIBTeX format since I use BibTool (version 2.32) by Gerd Neugebauer (a really nice tool!) to keep the bibliography in a consistent state. For us it is most convenient if you send raw BIBTeX files.
• BibTool automatically generates reference keys for the entries in the database. The old keys contained in the entries received are thrown away. Therefore, just do not worry about the format you use for keys. For reasons of consistency, all old entries remain in the file and keep their reference keys.
• Every new entry gets an additional field named added = {<year-month-day-hour-minute-second>} when it is included.
• Entries which are completely new are just added to the database (extended by the added field). Entries which were already present (which is detected using the option of BibTool that makes it find double entries) are treated differently. The automatic procedure (which will be improved by hand whenever possible) is that these entries are also added, while the old entry is extended by a new field named ATTENTION = {newer record added: <date>}. (Note that, according to the way BIBTeX works, the contents of the new fields will not affect the output of BIBTeX. They are just meant to provide useful information.)
• Entries are considered as double entries (that is, are assumed to refer to the same article) if they have equal authors (or editors) and titles, the entry types (@ARTICLE, @INPROCEEDINGS, etc.) are equal, and, if present in at least one of them, the JOURNAL fields coincide. Note that the year is not relevant! Hopefully, these rules will work well. If they do not, the problems caused should not be too serious, because no old entries are deleted in the database, anyway.
• A meta-rule: The rules above may be changed if experience reveals that something should better be handled in a different way.