"Links, Lags and Ladders - the subtleties of overlapping tasks" by Patrick Weaver
Abstract:
This paper is designed to help explain the subtleties of overlapping tasks.
Logic in a Precedence Network Precedence diagrams use boxes to represent the basic network elements - the task (or activity).
Tasks have durations giving the period of time required to perform the work they represent and may have other descriptive data attached to them.