俱舍論頌疏論本 15.63

15.63

餘說下亦有，由中招異熟者，有餘師說：第三禪下亦有第三順、非二業，中謂中間禪也。由中定業招中異熟故，明知下地有不苦不樂受業，謂生中間唯有捨受，故彼業感順、非二果。

"Others say it exists below as well, / Because the intermediate incurs maturation": other masters say that below the third dhyāna there is also the third karma, conducive to neither; "intermediate" refers to the intermediate dhyāna. Because the karma of the intermediate dhyāna incurs the maturation of the intermediate, it is clearly known that the lower stages have karma of neither-painful-nor-pleasant feeling, for birth in the intermediate has only the feeling of equanimity; hence that karma incurs a fruit conducive to neither.