This study examines the integration of heterogeneous bibliographic information resources from geographically distributed locations in an automated, unified, and controlled way using abstract data types called "classes" through the Message-Object Model defined in Smalltalk-80 software. The concept of achieving data consistency by developing classes for each type of information in a bibliographic citation, such as "date" or "title," is discussed as a method of simplifying the programmer's task; previous methods for processing heterogeneous bibliographic information are summarized; and the message-object model is defined. Finally, a detailed description is provided of the development of prototype classes using the Objective-C compiler based on the Smalltalk-80 Message-Object Model and the use of the prototype classes to integrate the citations retrieved from six online databases. Twenty-one references are provided, and the text is supplemented with four tables and three diagrams. Appendices include: (1) the hierarchy of Objective-C Classes; (2) the Objective-C base tree; (3) the prototype source code; and (4) a copy of the merged file of heterogeneous bibliographic citations from six database sources. (KM)