Chuck and Jan Rosenak are widely regarded as authorities in the field of American folk art. They amassed one of the finest collections of contemporary folk art in the United States and authored four books: Museum of American Folk Art Encyclopedia of Twentieth-Century American Folk Art and Artists (New York: Abbeville, 1990), The People Speak: Navajo Folk Art (Flagstaff, Arizona: Northland Publishing, 1994), Contemporary American Folk Art: A Collector's Guide (New York: Abbeville, 1996), and The Saint Makers: Contemporary Santeras y Santeros (Flagstaff, Arizona: Northland Publishing, 1998).