Rolf (FWD) Ludvigsen

title	ISBN-13 (ISBN-10)	year of publica- tion	other author(s)
Trilobites of New York: An Illustrated Guide	978-O-8O14-3969-8 (O-8O14-3969-8)	2002	Thomas E. Whiteley · Gerald J. Kloc · Carlton E. Brett