長阿含經 10.p119

10.p119

“Without an inner perception of form, one observes external form to be white. The white form, white reflection, and white sight are like a white flower or a white Vārāṇasī cloth. They are completely white forms, white reflections, and white sights. Creating such a perception, one continuously observes and attends to it. This is the eighth change to the senses.