%0 Journal Article %A Sherk, F. A. %A Pabst, Günther %T Indicator Sets, Reguli, and a New Class of Spreads %J Canadian journal of mathematics %D 1977 %P 132-154 %V 29 %N 1 %U http://geodesic.mathdoc.fr/articles/10.4153/CJM-1977-013-6/ %R 10.4153/CJM-1977-013-6 %F 10_4153_CJM_1977_013_6