ASHRAE Product Specification File 1981

age-toned : Used to describe a light brown or tan color that paper can sometimes assume as a result of age.

foxed : A discoloration to paper, brown and yellowish spots.

quarto : A term used generally to describe the approximate size of a book, a book that is about 10" to 12" tall and roughly squarish in shape. The term is based on the size of paper traditionally used by book printers which has been folded and cut into 16 pages.