1. Baer, R.: Zur Einführung des Scharbegriffs. J. Reine Angew. Math. 163, 199–207 (1929)
2. Behanzin, L.: Quelques considérations sur la théorie des demi-amas. Sém. Dubreil. Alg. th. Nomb. 12(3), 1–18 (1958–1959)
3. Bertram, W., Kinyon, M.: Associative geometries I: grounds, linear relations and Grassmannians. J. Lie Theory 20(2), 215–252 (2010)
4. Birkhoff, G., Bennett, M.K.: Felix Klein and his “Erlanger Programm”. In: Aspray, W., Kitcher, P. (eds.) History and Philosophy of Modern Mathematics. Minnesota Studies in the Philosophy of Science, vol. XI, pp. 145–176. University of Minnesota Press, Minneapolis (1988)
5. Bourbaki, N.: Théorie des Ensembles. Hermann, Paris (1939)