/usr/include/CLucene/snowball/src_c/ is in libclucene-dev 2.3.3.4-4.
This file is owned by root:root, with mode 0o755.
..
/usr/include/CLucene/snowball/src_c/stem_ISO_8859_1_danish.h
/usr/include/CLucene/snowball/src_c/stem_ISO_8859_1_dutch.h
/usr/include/CLucene/snowball/src_c/stem_ISO_8859_1_english.h
/usr/include/CLucene/snowball/src_c/stem_ISO_8859_1_finnish.h
/usr/include/CLucene/snowball/src_c/stem_ISO_8859_1_french.h
/usr/include/CLucene/snowball/src_c/stem_ISO_8859_1_german.h
/usr/include/CLucene/snowball/src_c/stem_ISO_8859_1_italian.h
/usr/include/CLucene/snowball/src_c/stem_ISO_8859_1_norwegian.h
/usr/include/CLucene/snowball/src_c/stem_ISO_8859_1_porter.h
/usr/include/CLucene/snowball/src_c/stem_ISO_8859_1_portuguese.h
/usr/include/CLucene/snowball/src_c/stem_ISO_8859_1_spanish.h
/usr/include/CLucene/snowball/src_c/stem_ISO_8859_1_swedish.h
/usr/include/CLucene/snowball/src_c/stem_KOI8_R_russian.h
/usr/include/CLucene/snowball/src_c/stem_UTF_8_danish.h
/usr/include/CLucene/snowball/src_c/stem_UTF_8_dutch.h
/usr/include/CLucene/snowball/src_c/stem_UTF_8_english.h
/usr/include/CLucene/snowball/src_c/stem_UTF_8_finnish.h
/usr/include/CLucene/snowball/src_c/stem_UTF_8_french.h
/usr/include/CLucene/snowball/src_c/stem_UTF_8_german.h
/usr/include/CLucene/snowball/src_c/stem_UTF_8_italian.h
/usr/include/CLucene/snowball/src_c/stem_UTF_8_norwegian.h
/usr/include/CLucene/snowball/src_c/stem_UTF_8_porter.h
/usr/include/CLucene/snowball/src_c/stem_UTF_8_portuguese.h
/usr/include/CLucene/snowball/src_c/stem_UTF_8_russian.h
/usr/include/CLucene/snowball/src_c/stem_UTF_8_spanish.h
/usr/include/CLucene/snowball/src_c/stem_UTF_8_swedish.h