Anushasana Parva 145.44

The various tribes of ghostly beings, as also all the embodied Rivers, and the Gandharvas and Apsaras, all bowed their heads to Mahadeva and departed for returning to the places whence they had come. The various tribes of ghostly beings, as also all the embodied Rivers, and the Gandharvas and Apsaras, all bowed their heads to Mahadeva and departed for returning to the places whence they had come.