/usr/lib/slepcdir/3.6.1/x86_64-linux-gnu-complex/include/slepc/finclude/ftn-auto/ is in libslepc-complex-3.6.1-dev 3.6.1.dfsg1-2build2.
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..
/usr/lib/slepcdir/3.6.1/x86_64-linux-gnu-complex/include/slepc/finclude/ftn-auto/slepcbv.h90
/usr/lib/slepcdir/3.6.1/x86_64-linux-gnu-complex/include/slepc/finclude/ftn-auto/slepcds.h90
/usr/lib/slepcdir/3.6.1/x86_64-linux-gnu-complex/include/slepc/finclude/ftn-auto/slepceps.h90
/usr/lib/slepcdir/3.6.1/x86_64-linux-gnu-complex/include/slepc/finclude/ftn-auto/slepcfn.h90
/usr/lib/slepcdir/3.6.1/x86_64-linux-gnu-complex/include/slepc/finclude/ftn-auto/slepcmfn.h90
/usr/lib/slepcdir/3.6.1/x86_64-linux-gnu-complex/include/slepc/finclude/ftn-auto/slepcnep.h90
/usr/lib/slepcdir/3.6.1/x86_64-linux-gnu-complex/include/slepc/finclude/ftn-auto/slepcpep.h90
/usr/lib/slepcdir/3.6.1/x86_64-linux-gnu-complex/include/slepc/finclude/ftn-auto/slepcrg.h90
/usr/lib/slepcdir/3.6.1/x86_64-linux-gnu-complex/include/slepc/finclude/ftn-auto/slepcst.h90
/usr/lib/slepcdir/3.6.1/x86_64-linux-gnu-complex/include/slepc/finclude/ftn-auto/slepcsvd.h90
/usr/lib/slepcdir/3.6.1/x86_64-linux-gnu-complex/include/slepc/finclude/ftn-auto/slepcsys.h90