Beyond this introduction, you will find the following two books essential to a mastery of the method and language:
Object-Oriented Software Construction , Bertrand Meyer, Prentice Hall, 2nd edition 1997. (Make sure to get the second edition.) About object technology in general; presents the method behind Eiffel.
Eiffel: The Language , Bertrand Meyer, Prentice Hall, 1992. Language manual and reference.
Numerous other books are available on Eiffel and Eiffel-related topics. See an extensive list at http://www.eiffel.com/doc/documentation.html , from which you can order most of the titles listed. They include university textbooks, general introductions, presentations of Eiffel projects, descriptions of libraries and other applications, books on BON and object-oriented methodology.
Copyright Interactive Software Engineering, 2001