Jay Jorgenson & Serge Lang 
The Heat Kernel and Theta Inversion on SL2(C) [PDF ebook] 

Gaussians, Spherical Inversion, and the Heat Kernel.- Spherical Inversion on SL2(C).- The Heat Gaussian and Heat Kernel.- QED, LEG, Transpose, and Casimir.- Enter ?: The General Trace Formula.- Convergence and Divergence of the Selberg Trace.- The Cuspidal and Noncuspidal Traces.- The Heat Kernel on ?/G/K.- The Fundamental Domain.- ?-Periodization of the Heat Kernel.- Heat Kernel Convolution on (?/G/K).- Fourier-Eisenstein Eigenfunction Expansions.- The Tube Domain for ??.- The ?/U-Fourier Expansion of Eisenstein Series.- Adjointness Formula and the ?/G-Eigenfunction Expansion.- The Eisenstein-Cuspidal Affair.- The Eisenstein Y-Asymptotics.- The Cuspidal Trace Y-Asymptotics.- Analytic Evaluations.