Pelzer, H., Niemeier, W., Fritzensmeier, K., Pelzer, H., & Niemeier, W. (1987). Determination of heights and height changes: Contributions to the Symposium on Height Determination and Recent Vertical Crustal Movements in Western Europe held at the University of Hannover, September 15-19, 1986. Bonn: Ferd. Dummler.

Pelzer, Hans, W. Niemeier, Klaus Fritzensmeier, Hans Pelzer, and W. Niemeier. Determination of Heights and Height Changes: Contributions to the Symposium On Height Determination and Recent Vertical Crustal Movements in Western Europe Held At the University of Hannover, September 15-19, 1986. Bonn: Ferd. Dummler, 1987.

Pelzer, Hans, et al. Determination of Heights and Height Changes: Contributions to the Symposium On Height Determination and Recent Vertical Crustal Movements in Western Europe Held At the University of Hannover, September 15-19, 1986. Bonn: Ferd. Dummler, 1987.