This sound effect can be found on Dimension Sound Effects Library, which was made by Sound Ideas. It is the same sound effect as Sound Ideas, ELEPHANT - ELEPHANT HERD: SMALL INDOOR GROUP ROARING, ANIMAL. Despite being labelled as an elephant sound, it is believed to actually have been recorded from lions. Two excerpts of this sound called Discovery Sound, DINOSAUR - Dinosaur-4 and Discovery Sound, COW - Cow-2 are found on Animal Sound Effects Library. Links: https://soundeffects.fandom.com/wiki/Sound_Ideas,_ANIMAL,_ELEPHANT_-_MANY_ELEPHANTS_IN_A_HERD#Audio_Samples