/usr/include/regina-normal/utilities/ is in regina-normal-dev 4.96-2.1build2.
This file is owned by root:root, with mode 0o755.
..
/usr/include/regina-normal/utilities/base64.h
/usr/include/regina-normal/utilities/bitmanip.h
/usr/include/regina-normal/utilities/boostutils.h
/usr/include/regina-normal/utilities/flags.h
/usr/include/regina-normal/utilities/i18nutils.h
/usr/include/regina-normal/utilities/intutils.h
/usr/include/regina-normal/utilities/memutils.h
/usr/include/regina-normal/utilities/nbitmask.h
/usr/include/regina-normal/utilities/nbooleans.h
/usr/include/regina-normal/utilities/nlistoncall.h
/usr/include/regina-normal/utilities/nmarkedvector.h
/usr/include/regina-normal/utilities/nmatrix2.h
/usr/include/regina-normal/utilities/nmpi.h
/usr/include/regina-normal/utilities/nproperty.h
/usr/include/regina-normal/utilities/nqitmask.h
/usr/include/regina-normal/utilities/nrational.h
/usr/include/regina-normal/utilities/nthread.h
/usr/include/regina-normal/utilities/ntrieset.h
/usr/include/regina-normal/utilities/ntritmask.h
/usr/include/regina-normal/utilities/nxmlcallback.h
/usr/include/regina-normal/utilities/nxmlelementreader.h
/usr/include/regina-normal/utilities/osutils.h
/usr/include/regina-normal/utilities/ptrutils.h
/usr/include/regina-normal/utilities/registryutils.h
/usr/include/regina-normal/utilities/stlutils.h
/usr/include/regina-normal/utilities/stringutils-impl.h
/usr/include/regina-normal/utilities/stringutils.h
/usr/include/regina-normal/utilities/stringutils.tcc
/usr/include/regina-normal/utilities/xmlutils.h
/usr/include/regina-normal/utilities/zstream.h