Ralph Lent Jeffery (3 October 1889 Overton, Yarmouth County, Nova Scotia, Canada – 1975 Wolfville, Nova Scotia) was a Canadian mathematician working on analysis.
He taught at several institutions including Acadia University, the University of Saskatchewan and Queen's University. Jeffery Hall at Queen's was named for him. In 1937 he was elected a Fellow of the Royal Society of Canada.
In 1925 Jeffery exhibited a bounded function of two real variables, continuous in each, yet fails to have an integral.
In 1951 Jeffery published Theory of Functions of a Real Variable which was noted for its coverage of integration theory.[1]