Waterfall

A model of the Software Design Life Cycle (SDLC) from the 1970s

Waterfall is often credited to a paper by William Royce called “Managing the Development of Large Software Systems”, which can be found here and here

Sources do not agree on whether this paper is from

• 1970 Proceedings of IEEE WESCON 26 (August): 1–9.
• 1. Proceedings of the 9th international conference on Software Engineering (ICSE ‘87).

(In any case, for undergrad students in the second or third decade of the 21st century, it hardly matters.)