/usr/ is in libsingular4-dev 4.0.3+ds-1.
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/usr/lib/
/usr/lib/x86_64-linux-gnu/
/usr/lib/x86_64-linux-gnu/pkgconfig/
/usr/lib/x86_64-linux-gnu/pkgconfig/singular-omalloc.pc
/usr/lib/x86_64-linux-gnu/pkgconfig/Singular.pc
/usr/lib/x86_64-linux-gnu/pkgconfig/singular-libpolys.pc
/usr/lib/x86_64-linux-gnu/pkgconfig/singular-resources.pc
/usr/lib/x86_64-linux-gnu/pkgconfig/singular-factory.pc
/usr/lib/x86_64-linux-gnu/libsingular-Singular.a
/usr/lib/x86_64-linux-gnu/libsingular-factory.a
/usr/lib/x86_64-linux-gnu/libsingular-resources.a
/usr/lib/x86_64-linux-gnu/libsingular-omalloc.a
/usr/lib/x86_64-linux-gnu/libsingular-polys.a
/usr/lib/x86_64-linux-gnu/libsingular-gfan.a
/usr/include/
/usr/include/x86_64-linux-gnu/
/usr/include/x86_64-linux-gnu/singular/
/usr/include/x86_64-linux-gnu/singular/factory/
/usr/include/x86_64-linux-gnu/singular/factory/factoryconf.h
/usr/include/x86_64-linux-gnu/singular/resources/
/usr/include/x86_64-linux-gnu/singular/resources/resourcesconfig.h
/usr/include/x86_64-linux-gnu/singular/singular/
/usr/include/x86_64-linux-gnu/singular/singular/libpolysconfig.h
/usr/include/x86_64-linux-gnu/singular/singular/singularconfig.h
/usr/include/x86_64-linux-gnu/singular/omalloc/
/usr/include/x86_64-linux-gnu/singular/omalloc/omConfig.h
/usr/share/
/usr/share/lintian/
/usr/share/lintian/overrides/
/usr/share/lintian/overrides/libsingular4-dev
/usr/share/doc/
/usr/share/doc/libsingular4-dev/
/usr/share/doc/libsingular4-dev/copyright
/usr/lib/x86_64-linux-gnu/pkgconfig/singular.pc
/usr/lib/x86_64-linux-gnu/libsingular-factory.so
/usr/lib/x86_64-linux-gnu/libsingular-omalloc.so
/usr/lib/x86_64-linux-gnu/libsingular-polys.so
/usr/lib/x86_64-linux-gnu/libsingular-resources.so
/usr/lib/x86_64-linux-gnu/libsingular-Singular.so
/usr/lib/x86_64-linux-gnu/libsingular-gfan.so
/usr/share/doc/libsingular4-dev/changelog.Debian.gz