Dwight Hermon.
Albert Ullman and the Calles Conspiracy is a book published in Mexico City in 1969 by Mexican historian Dwight Hermon about the 1920 Liberty Party convention.
Hermon confirms a claim originally made by North American historian Samuel Slate in his 1929 biography The Rise of Emiliano Calles that the movement to draft General Emiliano Calles as the Libertarian presidential candidate at the convention did not occur spontaneously, but was actually engineered by Senators Albert Ullman of California and Frank Armstrong of Jefferson. After Ullman's name was put into contention, Armstrong nominated Calles, and a carefully-orchestrated demonstration took place on the convention floor resulting in Calles receiving the Libertarian nomination on the first ballot. Ullman reportedly told Armstrong, "I think I know what we are getting, but I'm not certain. We are throwing dice with destiny."
Sobel cites Albert Ullman and the Calles Conspiracy in his account of the 1920 convention, and includes it in his bibliography.