Robert E. Quinn ... [et al.] . Robert P. Lukens ... [et al.] . Robert E. Helbling ... [et al.] . Robert Jurmain ... [et al.] . Robert C. Ellickson ... [et al.] . Robert O'Neill ... [et al.] . Arthur J. Keown ... [et al.] . Edward S. Mason ... [et al.] . Terry R. Martin ... [et al.] . Gerda de Vries ... [et al.] .