Michael Berkeley 's guest this week is crime writer Michael Dibdin , whose new book, A Long Finish - the latest in his popular mystery series featuring the Italian detective Aurelio Zen - is published this month. His choices range from vocal music by Dufay, Palestrina and Vivaldi to Britten's Cello Symphony and a vaudeville by Charles Dibdin , an 18th-century British composer who may have been a distant ancestor. Executive producer Wendy Thompson Repeated tomorrow 6.30pm