If you want a book designed for the professional, as opposed to the recreational skiier or climber, I would check out the <b>Avalanche Handbook</u> by Dave McClung and Peter Schearer. They know their stuff. McClung in particular was head of avalanche control in Rogers Pass for 10 years, additionally has climbed 8000m peaks and put up the "Peruvian Headwall" finish to the Price Glacier roue on Shuksan.