Dirk Nowitzki scored the 20 points he needed for 30,000 in his career in barely more than a quarter, and the Dallas Mavericks celebrated with their second straight easy home win over the Los Angeles Lakers, a 122-111 victory Tuesday night. The 7-foot German became the sixth NBA player and the first international one to reach the milestone, joining four Hall of Famers and a future one in Kobe Bryant.