Whittaker's letters home from Trinity College, Cambridge, 1896 (transcribed by Roger Cook)
Scans of some of the original letters
On the Connexion of Algebraic Functions with Automorphic Functions Whittaker's thesis, Phil. Trans. of the Royal Society 192, 1-32. (3) 1900
Whittaker is commemorated in the School of Mathematics by the annual Whittaker Colloquium, the Whittaker Research Fellowships, the Whittaker Chair, as well as by the Whittaker Prize of the Edinburgh Mathematical Society.
Speakers in the Whittaker Colloquium have included Gunnar Carlsson, Robbert Dijkgraaf, Peter Kronheimer, Philip Maini, Richard Melrose, Janos Pintz, Endre Szemeredi, Terence Tao and Sir Christopher Zeeman.
The 2012 Whittaker Colloquium speaker was John Stillwell, who gave two lectures, the first of which featured Whittaker's work:
From Poincare to Whittaker to Ford : slides, video
Poincare and the early history of 3-manifolds : slides, video