CC Madhya 16.214-215

tāra madhye mililā yaiche rūpa-sanātana
nṛsiṁhānanda kaila yaiche pathera sājana
sūtra-madhye sei līlā āmi ta’ varṇiluṅ
ataeva punaḥ tāhā ihāṅ nā likhiluṅ
Synonyms: 
tāra madhye — within that; mililā — He met; yaiche — how; rūpa-sanātana — the two brothers Rūpa and Sanātana; nṛsiṁhānanda — Nṛsiṁhānanda; kaila — did; yaiche — how; pathera sājana — decoration of the road; sūtra-madhye — in the synopsis; sei līlā — those pastimes; āmi — I; ta’ — indeed; varṇiluṅ — have described; ataeva — therefore; punaḥ — again; tāhā — that; ihāṅ — here; likhiluṅ — I have not written.
Translation: 
Those narrations tell how Śrī Caitanya Mahāprabhu met the brothers Rūpa and Sanātana and how Nṛsiṁhānanda decorated the road. I have already described these in an earlier synopsis of this book; therefore I will not repeat the narrations here.
Purport: 

This information is given in Ādi-līlā 10.35 and Madhya-līlā 1.155-162 and 175-226.