/usr/include/cereal/external/ is in libcereal-dev 1.2.1-2.
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/usr/include/cereal/external/base64.hpp
/usr/include/cereal/external/rapidjson/
/usr/include/cereal/external/rapidjson/allocators.h
/usr/include/cereal/external/rapidjson/document.h
/usr/include/cereal/external/rapidjson/encodedstream.h
/usr/include/cereal/external/rapidjson/encodings.h
/usr/include/cereal/external/rapidjson/error/
/usr/include/cereal/external/rapidjson/error/en.h
/usr/include/cereal/external/rapidjson/error/error.h
/usr/include/cereal/external/rapidjson/filereadstream.h
/usr/include/cereal/external/rapidjson/filewritestream.h
/usr/include/cereal/external/rapidjson/fwd.h
/usr/include/cereal/external/rapidjson/internal/
/usr/include/cereal/external/rapidjson/internal/biginteger.h
/usr/include/cereal/external/rapidjson/internal/diyfp.h
/usr/include/cereal/external/rapidjson/internal/dtoa.h
/usr/include/cereal/external/rapidjson/internal/ieee754.h
/usr/include/cereal/external/rapidjson/internal/itoa.h
/usr/include/cereal/external/rapidjson/internal/meta.h
/usr/include/cereal/external/rapidjson/internal/pow10.h
/usr/include/cereal/external/rapidjson/internal/regex.h
/usr/include/cereal/external/rapidjson/internal/stack.h
/usr/include/cereal/external/rapidjson/internal/strfunc.h
/usr/include/cereal/external/rapidjson/internal/strtod.h
/usr/include/cereal/external/rapidjson/internal/swap.h
/usr/include/cereal/external/rapidjson/istreamwrapper.h
/usr/include/cereal/external/rapidjson/memorybuffer.h
/usr/include/cereal/external/rapidjson/memorystream.h
/usr/include/cereal/external/rapidjson/msinttypes/
/usr/include/cereal/external/rapidjson/msinttypes/inttypes.h
/usr/include/cereal/external/rapidjson/msinttypes/stdint.h
/usr/include/cereal/external/rapidjson/ostreamwrapper.h
/usr/include/cereal/external/rapidjson/pointer.h
/usr/include/cereal/external/rapidjson/prettywriter.h
/usr/include/cereal/external/rapidjson/rapidjson.h
/usr/include/cereal/external/rapidjson/reader.h
/usr/include/cereal/external/rapidjson/schema.h
/usr/include/cereal/external/rapidjson/stream.h
/usr/include/cereal/external/rapidjson/stringbuffer.h
/usr/include/cereal/external/rapidjson/writer.h
/usr/include/cereal/external/rapidxml/
/usr/include/cereal/external/rapidxml/manual.html
/usr/include/cereal/external/rapidxml/rapidxml.hpp
/usr/include/cereal/external/rapidxml/rapidxml_iterators.hpp
/usr/include/cereal/external/rapidxml/rapidxml_print.hpp
/usr/include/cereal/external/rapidxml/rapidxml_utils.hpp