KANSAS CITY, MO.- The baseball league that helped spark integration of American professional sports is being honored today on a 44-cent U.S. postage stamp being issued at the Negro Leagues Baseball Museum. The Negro Leagues Baseball stamps pay tribute to the all-black professional baseball leagues that operated from 1920 to about 1960. A second commemorative stamp features the league’s founder, Andrew “Rube” Foster, who is considered the “father” of Negro Leagues Baseball. In 1981, Foster was honored by the National Baseball Hall of Fame as the “foremost manager and executive” of Negro Leagues baseball. “The United States Postal Service is honored to be dedicating two stamps today in commemoration of Negro Leagues Baseball,” said Thurgood Marshall Jr., the Postal Service’s Board of Governors vice chairman. “In 1920, the first of several black leagues of the modern era was form