Reference for Menachot 85:12
מדרמי קסבר מצות עשה שלא הזמן גרמא הוא אמאי מברך כל צפרא וצפרא
But since he attached [the fringes to the womens' garments], obviously he is of the opinion that it is a precept not dependent on a fixed time;<span class="x" onmousemove="('comment',' For women must observe only those positive precepts that do not depend upon the time of the year or of the day for their performance; therefore by imposing the precept of zizith upon women Rab Judah obviously holds that night as well as day is the proper time for the fringes.');"><sup>15</sup></span> why then did he say the blessing every morning?<span class="x" onmousemove="('comment',' Surely the blessing should be said only once, and that when the garment is put on for the first time.');"><sup>16</sup></span>