/usr/include/liblas/detail/ is in liblas-dev 1.8.1-3+b1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/liblas/detail/binary.hpp
/usr/include/liblas/detail/endian.hpp
/usr/include/liblas/detail/file_ptr_stream.hpp
/usr/include/liblas/detail/fwd.hpp
/usr/include/liblas/detail/index/
/usr/include/liblas/detail/index/indexcell.hpp
/usr/include/liblas/detail/index/indexoutput.hpp
/usr/include/liblas/detail/opt_allocator.hpp
/usr/include/liblas/detail/pointrecord.hpp
/usr/include/liblas/detail/private_utility.hpp
/usr/include/liblas/detail/reader/
/usr/include/liblas/detail/reader/cachedreader.hpp
/usr/include/liblas/detail/reader/header.hpp
/usr/include/liblas/detail/reader/reader.hpp
/usr/include/liblas/detail/reader/zipreader.hpp
/usr/include/liblas/detail/sha1.hpp
/usr/include/liblas/detail/singleton.hpp
/usr/include/liblas/detail/timer.hpp
/usr/include/liblas/detail/writer/
/usr/include/liblas/detail/writer/header.hpp
/usr/include/liblas/detail/writer/point.hpp
/usr/include/liblas/detail/writer/writer.hpp
/usr/include/liblas/detail/writer/zipwriter.hpp
/usr/include/liblas/detail/zippoint.hpp