Paramagnetic Spectra of Substituted Sapphires—Part 1: Ruby

Some Measurements of the Decay of Paramagnetic Saturation in Synthetic Ruby

Electron Paramagnetic Resonance Studies of Coherent Optical Transitions in Ruby.

Paramagnetic resonant frequency mixing in ruby

Absorption and emission spectra of ruby in excited states

Infrared Absorption Spectra from Excited States in Ruby

Changes in the Absorption Spectra of Ruby at High Excitation Levels