Srimad Bhagavatam Canto 03, Chapter 01, Text 22

SB 3.1.22

tasyam tritasyosanaso manos ca
prthor athagner asitasya vayoh
tirtham sudasasya gavam guhasya
yac chraddhadevasya sa asiseve
 
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
 
On the bank of the river Sarasvati there were eleven places of pilgrimage, namely (1) Trita, (2) Usana, (3) Manu, (4) Prthu, (5) Agni, (6) Asita, (7) Vayu, (8) Sudasa, (9) Go, (10) Guha and (11) Sraddhadeva. Vidura visited all of them and duly performed rituals.
Srimad Bhagavatam Canto 03, Chapter 01, Text 21
Srimad Bhagavatam Canto 03, Chapter 01, Text 23