Lon Chaney Sr.'s horrifying visage as Erik, the Phantom of the Paris Opera House, was pervasive. Here we see two swipes from "photo references" used by Spanish artists for book covers (from the Spanish Book Covers Blog).
One is from Red Dot Books titled The Fear Syndrome by Curtis Garland, a pseudonym of Juan Gallardo Munoz. Munoz was born in Barcelona, Spain on October 28, 1929. He is known there for his mystery, science-fiction and horror novels.
The other is "The History of Dr. Death" from a publication entitled Terror.