Addendum: PSA/DNA authenticated it as a 1937 A.L. All-Star team ball. Based on the signatures, it appears to be member of the 1938 A.L. squad.
The 1938 All-Star Game was played at Crosley Field in Cincinnati, OH on July 6, 1938. The National League prevailed in the sixth Mid-Summer Classic by the score of 4-1 in a swiftly played 1-hour, 58-minute contest. NL starter Johnny Vander Meer and Bill Lee combined to pitch six shutout innings, outdueling AL starter Lefty Gomez and relievers Johnny Allen and Lefty Grove. AL shortstop Joe Cronin (2-3, RBI) and NL catcher Ernie Lombardi (2-4, RBI) paced each offense.
Presented here is 1938 American League All-Star team signed baseball with 25 signatures. Eleven Hall of Famers including Jimmie Foxx, Joe DiMaggio, Hank Greenberg, Bob Feller, Cronin, Grove, Gomez, Bill Dickey, Chas Gehringer, Rick Ferrell and Red Ruffing have blessed it, along with other notables like Allen, Johnny Murphy, Doc Cramer, Red Rolfe, Bob Johnson, Rudy York, Vern Kennedy, Buddy Lewis, Cecil Davis, Dave Keefe, Del Baker, Buck Newsom and Art Fletcher. Gehrig is missing and Earl Averill has been deemed clubhouse. The black penned signatures range mostly 6-7/10 on this evenly toned, cream-colored OAL (Harridge) ball with a light coating of shellac.
Full LOA from PSA/DNA (who calls it a '37 AL team ball). Part of Ossie Vitt Collection and includes letter of provenance from Vitt's grandson.