L. P. Sikkel
- Aspects of quality and quality assurance in tendering and contracting. Présenté pendant: IABSE Symposium: Safety and Quality Assurance of Civil Engineering Structures = Sécurité et assurance de la qualité des structures de génie civil = Sicherheit und Qualitätssicherung von Ingenieurbauwerken, Tokio, Japan, 1986. (1986):
- The importance of the organization in the design and construction process of large projects. Présenté pendant: 11th IABSE Congress, Vienna, Austria, 31 August - 5 September 1980. (1980):
- Project management and construction management. Présenté pendant: 11th IABSE Congress, Vienna, Austria, 31 August - 5 September 1980. (1980):