Free extensions of double categories R. J. M. Dawson; R. Pare; D. A. Pronk — 2004 Cahiers de Topologie et Géométrie Différentielle Catégoriques
Universal properties of Span. Dawson, R.J.MacG.; Paré, R.; Pronk , D.A. — 2004 Theory and Applications of Categories [electronic only]
Paths in double categories. Dawson, R. J. MacG.; Paré, R.; Pronk, D. A. — 2006 Theory and Applications of Categories [electronic only]