€ 6,00
32 p.; ills. Wrs. (Offpr. Water en Gas, 5/6, 1930)
Den Haag, 1930.
Amst., Swets & Zeitlinger, 1942.
Amsterdam, NHUM, 1986.
Ann Arbor, University of Michigan Press, (1959).
Chicago, Argonaut, 1967.