Actually, it IS available at CPDL. "O Crux Ave" is one of the verses of "Vexilla Regis" and, as such, it is found in the Victoria settings by that name."O Crux Ave" (SATB) by Victoria is a beautiful Lenten piece. Rather hard to find resources for this, online, but I managed to find a recording. So far I haven't seen it on CPDL.
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