Magda Ševčíková-Razímová, Zdeněk Žabokrtský (2006):Systematic Parameterized Description of Pro-forms in the Prague Dependency Treebank 2.0. In: Proceedings of the Fifth Workshop on Treebanks and Linguistic Theories (TLT), pp. 175-186, ÚFAL MFF UK, Praha, Czechia, ISBN 80-239-8009-2 (pdf, bibtex)