Gutsherr und Untertan : in der Mittelmark Brandenburg zu Beginn der Bauernbefreiung. - Spies, Klaus (Abha, Survey of educational institutions with recreation facilities open to the general public or any outside organisations; no.3, Home interview survey of demands for recreation facilities; no.4, Use of facilities survey; no.5, Secondary school students survey. / (Munchener Universitatsschriften; Juristische Fakultat, 1972)