/usr/include/ql/legacy/ is in libquantlib0-dev 1.12-1.
This file is owned by root:root, with mode 0o755.
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/usr/include/ql/legacy/all.hpp
/usr/include/ql/legacy/libormarketmodels/
/usr/include/ql/legacy/libormarketmodels/all.hpp
/usr/include/ql/legacy/libormarketmodels/lfmcovarparam.hpp
/usr/include/ql/legacy/libormarketmodels/lfmcovarproxy.hpp
/usr/include/ql/legacy/libormarketmodels/lfmhullwhiteparam.hpp
/usr/include/ql/legacy/libormarketmodels/lfmprocess.hpp
/usr/include/ql/legacy/libormarketmodels/lfmswaptionengine.hpp
/usr/include/ql/legacy/libormarketmodels/liborforwardmodel.hpp
/usr/include/ql/legacy/libormarketmodels/lmconstwrappercorrmodel.hpp
/usr/include/ql/legacy/libormarketmodels/lmconstwrappervolmodel.hpp
/usr/include/ql/legacy/libormarketmodels/lmcorrmodel.hpp
/usr/include/ql/legacy/libormarketmodels/lmexpcorrmodel.hpp
/usr/include/ql/legacy/libormarketmodels/lmextlinexpvolmodel.hpp
/usr/include/ql/legacy/libormarketmodels/lmfixedvolmodel.hpp
/usr/include/ql/legacy/libormarketmodels/lmlinexpcorrmodel.hpp
/usr/include/ql/legacy/libormarketmodels/lmlinexpvolmodel.hpp
/usr/include/ql/legacy/libormarketmodels/lmvolmodel.hpp