Srimad Bhagavatam Canto 03, Chapter 12, Text 52

SB 3.12.52

evam yukta-krtas tasya
 daivam caveksatas tada
kasya rupam abhud dvedha
 yat kayam abhicaksate
 
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
 
While he was thus absorbed in contemplation and was observing the supernatural power, two other forms were generated from his body. They are still celebrated as the body of Brahma.
 
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
 
Two bodies came out from the body of Brahma. One had a mustache, and the other had swollen breasts. No one can explain the source of their manifestation, and therefore until today they are known as the kayam, or the body of Brahma, with no indication of their relationship as his son or daughter.
Srimad Bhagavatam Canto 03, Chapter 12, Text 51
Srimad Bhagavatam Canto 03, Chapter 12, Text 53