text: During his tenure , the Philharmonic enjoyed a period of unprecedented success and prosperity and performed its first world premiere written by a world-renowned composer in the United States â `` AntonÃ n DvoÅ Ã k 's Ninth Symphony `` From the New World '' .
simplified: He gave the first performance of AntonÃ n DvoÅ Ã k 's Ninth Symphony `` From the New World . ''