Reference for Menachot 75:7

ורבנן וראיתם אותו כל חד לחודיה משמע

[which implies that the fringes must be] of the same [colour] as that of the corner,<span class="x" onmousemove="('comment',' As garments were usually of white linen, there must therefore be white threads as fringes.');">⁷</span> and it also says, A blue thread;<span class="x" onmousemove="('comment',' Ibid. 38.');">⁶</span>

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