Gandharan Art in Context: East West Exchanges at the Crossroads of Asia, By Raymond Allchin, Bridget Allchin, Neil Kreitman and Elisabeth Errington

Proceedings from an exhibition at the Fitzwilliam Museum in Cambridge, 1992."The Crossroads of Asia"
with contributions by John Boardman, Chaibai Mustamandy, B. Staviski, Karl Jettmar, Martha L. Carter, Doris MethSrinivasan, Shoshin Kurwayama, B.N. Mukherjee, Osmund Bopearachchi, Joe Cribb, David W. Mac Dowall, E.V. Zeymal, Chandra L. Reedy, Mark I. Wypyski

Central Asia, Afghanistan, Bactria, Coinage, Sculpture, Textiles, Stupas, Technique. 
Important academic research. Hard to find!