Complex sentence: Softcover Bestseller The thirtieth mystery- "Mrs. Jeffries Defends Her Own" was published-as an orignal paperback-in May 2012 and made the New York Times Mass Market Fiction Bestseller List-for May 20th 2012.
Split into simpler sentences: Softcover Bestseller The thirtieth mystery in the series is "Mrs. Jeffries Defends Her Own" published-as a paperback-in May 2012. The book made the New York Times Mass Market Fiction Bestseller List-May 20th 2012.