Join PSA and PSA/DNA at the 31st National Sports Collectors Convention in Baltimore, Maryland August 4 – 8, 2010. On-site card grading, On-site autograph authentication and grading, Quantity discounts, and special guests Saturday, August 7. Visitors to the 2010 National Sports Collectors Convention will have an opportunity to see an exhibit of rare Babe Ruth baseball cards and also have an opportunity to receive a free magazine and book from Professional Sports Authenticator (www.PSAcard.com). “Baltimore is the birthplace of Babe Ruth. PSA will pay tribute to ‘The Sultan of Swat’ by displaying classic 1930s era Goudey, Sport Kings and U.S. Caramel cards of Ruth as well as seldom-seen 1920s American Caramel and other candy and ice cream Ruth cards from the collection of PSA Set Registry Hall of Fame honoree, Donald E. Spence of Texas,” said Joe Orlando, President of PSA, a division of Collectors Universe, Inc.