I am aware that making that distinction narrows the google search. However, I am looking at my bookshelf just a few feet away, and I don't see one single classic(al) guitar technique manual (Aaron Shearer's set, Frederick Noad's, Carcassi, Aquado, the complete Fernando Sor studies, manuals by Ricardo Iznaola, Eduardo Fernandez, and several others) that has "Classical" on the cover. They all say "Classic."

Don Firth