Srimad Bhagavatam Canto 09, Chapter 08, Text 28

SB 9.8.28

sri-bhagavan uvaca
asvo ’yam niyatam vatsa
 pitamaha-pasus tava
ime ca pitaro dagdha
 gangambho ’rhanti netarat
 
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
 
The Personality of Godhead said: My dear Amsuman, here is the animal sought by your grandfather for sacrifice. Please take it. As for your forefathers, who have been burnt to ashes, they can be delivered only by Ganges water, and not by any other means.
 
Srimad Bhagavatam Canto 09, Chapter 08, Text 27
Srimad Bhagavatam Canto 09, Chapter 08, Text 29