Dai Tri Man Le Ryszard Janicki A Categorical Approach to Mereology and Its Application to Modelling Software Components. 146-174 2008 8 T. Rough Sets http://dx.doi.org/10.1007/978-3-540-85064-9_8 journals/trs/2008-8 db/journals/trs/trs8.html#LeJ08