IV.—The C Discriminant as an Envelope

James A. Macdonald
1900 Transactions of the Royal Society of Edinburgh  
The purpose of this paper is to discuss the conditions under which the C discriminant of a system of curves furnishes a curve which at every point of its length is touched by a curve of the system.
doi:10.1017/s0080456800034037 fatcat:crncosmitfhhhfvqpjocqzc3su