He mentions reference to it in that book,
this reference is in DN15: Maha Nidana Sutta.
This is quotation from DN15:
there were none of the features, attributes, signs, and details by which the categories of mental or physical phenomena are found. Would either linguistic contact or impingement contact still be found?”
“Yehi, ānanda, ākārehi …pe… yehi uddesehi nāmakāyassa ca rūpakāyassa ca paññatti hoti, tesu ākāresu …pe… tesu uddesesu asati api nu kho adhivacanasamphasso vā paṭighasamphasso vā paññāyethā”ti?