Integrated Specification of Method and Graphic Knowledge. - Arthur H. M. ter Hofstede; T. F. Verhoef; E. R. Nieuwland; G. M. Wijers (SEKE, 1992)

Task structure semantics through process algebra. - Arthur H. M. ter Hofstede; E. R. Nieuwland (Softw. Eng. J., 1993)