Wide components in double and multiple stars proceedings of the 97th Colloquium of the International Astronomical Union, held in Brussels, Belgium, 8-13 June, 1987 - Dommanget, J. (edited); Dessel, E. L. van (Edwin Ludo), 1943-; Kopal, Zdeněk, 1914-1993 (Kluwer Academic Publishers, 1988)