$43
The original "The Firebird Book: a Reference for Database Developers" written by Helen Borrie, was published by Apress in 2004, to rave reviews.
The new and revised second edition largely follows the organisation of the original, packaging the Firebird essentials and know-how in eight parts, each consisting of groups of chapters reflecting a typical workflow for developers learning a database management system in new territory. More than a dozen appendices provide quick reference to facts, error codes, internal and external functions and more. This new edition provides a similarly useful desktop reference to its predecessor for most levels of professional user.