  Two methods for extracting detailed formal dependencies from the Coq and
Mizar system are presented and compared. The methods are used for dependency
extraction from two large mathematical repositories: the Coq Repository at
Nijmegen and the Mizar Mathematical Library. Several applications of the
detailed dependency analysis are described and proposed. Motivated by the
different applications, we discuss the various kinds of dependencies that we
are interested in,and the suitability of various dependency extraction methods.
