瑜伽論記 6.434

6.434

基師又云：無問鳥獸之細毛皆曰毳，恐三衣以無價疊等為，故以毳毛為之也。此文或是長衣，故知杜多亦有長毳衣，應須說淨也，阿練若名空閑處，去村一拘盧舍半。

Master Ji also says: the fine hair of either birds or beasts is called *cui*; fearing that the three robes might be made of priceless cloth or the like, one uses fleece to make them. This text may refer to extra robes; hence one knows that in *dhūta* practice there are also extra woolen robes, which must undergo the rite of purifying determination. *Araṇya* means an empty and quiet place, one and a half *krośas* away from a village.