Proceedings of the 76th annual road school, West Lafayette(In), Mar.6-8, 1990 / Road school (76; 1990; West Lafayette(In)), 1990. - 129 p. - Текст : непосредственный.
Proceedings of the 78th annual road school,West Lafayette(In),March 10-12,1992 / Scairmen:C.F.Scholler, 1992. - 85 p. - Текст : непосредственный.
Proceedings of the 79th annual road school,March 2-4,1993,West Lafayette(In) / Road school (79; 1993; West Lafayette,In.), 1993. - 52 p. - Текст : непосредственный.