Hüdraulika ja pumbadMaastik, Aleksander; Haldre, Heiti; Koppel, Tiit; Paal, Leopold1995 https://www.ester.ee/record=b1068996*est

Lugupeetud professor Harald VelneristHaldre, Heiti; Maastik, AleksanderHarald-Adam Velner - insener ja veeteadlane1993 / lk. 29-30 https://www.ester.ee/record=b1053756*est

To our senior, professor Harald VelnerHaldre, Heiti; Maastik, AleksanderHarald-Adam Velner - engineer and scientist1994 / p. 31-32 https://www.ester.ee/record=b1053757*est