SOMERVILL, B. A. (2006). WILLIAM PENN FOUNDER OF PENNSYLVANIA. COMPASS POINT BOOKS.
芝加哥风格引文SOMERVILL, BARBARA. A. WILLIAM PENN FOUNDER OF PENNSYLVANIA. MINNEAPOLIS: COMPASS POINT BOOKS, 2006.
MLA引文SOMERVILL, BARBARA. A. WILLIAM PENN FOUNDER OF PENNSYLVANIA. COMPASS POINT BOOKS, 2006.
警告：这些引文格式不一定是100％准确.