俱舍論記 9.205

9.205

「次與境合至順樂等觸」者，出觸支體。既六根生次與境合便有識生，根、境、識合有順樂受等三觸。

"Next, conjoining with the sense objects... contact conforming to pleasure and so on": this identifies the substantial nature of the limb of contact. Once the six sense faculties have arisen, they next conjoin with sense objects, whereupon consciousness arises; the coming together of faculty, object, and consciousness constitutes the three kinds of contact, such as that which conforms to pleasant feeling.