Note, there are two further volumes that are only available from World Scientific Publishing.
Yang-Baxter Equations, Conformal Invariance and Integrability in Statistical Mechanics and Field Theory, edited by Michael Barber and Paul Pearce, 1989
Miniconference on Chaos and Order, edited by Nalini Joshi and R.L. Dewar, 1990
The Mathematical Sciences Institute regularly publishes symposia proceedings, surveys and monographs in the series Proceedings of the CMA. Volumes are available to download for free.