/usr/share/doc/libplexus-compiler-java/api/org/codehaus/plexus/compiler/csharp/ is in libplexus-compiler-java-doc 1.9.2-2.
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/usr/share/doc/libplexus-compiler-java/api/org/codehaus/plexus/compiler/csharp/CSharpCompiler.html
/usr/share/doc/libplexus-compiler-java/api/org/codehaus/plexus/compiler/csharp/DefaultCSharpCompilerParser.html
/usr/share/doc/libplexus-compiler-java/api/org/codehaus/plexus/compiler/csharp/class-use/
/usr/share/doc/libplexus-compiler-java/api/org/codehaus/plexus/compiler/csharp/class-use/CSharpCompiler.html
/usr/share/doc/libplexus-compiler-java/api/org/codehaus/plexus/compiler/csharp/class-use/DefaultCSharpCompilerParser.html
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/usr/share/doc/libplexus-compiler-java/api/org/codehaus/plexus/compiler/csharp/package-tree.html
/usr/share/doc/libplexus-compiler-java/api/org/codehaus/plexus/compiler/csharp/package-use.html