Complex expressions, as used in mathematics and logics, account for a large part of human knowledge. It is therefore desirable to allow for their representation and search in RDF. We propose an approach that fulfills three objectives: (1) the accurate representation of expressions in standard RDF, so that expressive search is made possible, (2) the automated generation of human-readable labels for expressions, and (3) the compatibility with legacy data (e.g., OWL/RDF, SPIN). (A long version of this paper is available at http://hal.inria.fr/hal-00812197.)