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DrScheme: Please download and use the DrScheme system embedded in Version 4.2.3.
To avoid compatability available from the PLT Scheme web site. To avoid compatibility problems, please make sure you use a Version numbered 4.2.x. 3 (as As of 2-1-11-10, the latest version )is 4.2.4, which fixes some bugs in 4.2.3.
Notes for Java: Object-oriented Design
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