I find it amusing now that traditionalist Roman Catholics will cite the story about the emissaries of St. Vladimir talking about the Divine Liturgy to support their claims regarding the EF of the Roman rite, when those emissaries were referring to the Byzantine Rite. In fact they were actually not impressed by what they saw when they visited the Romans and the Franks.

His feast day was just last week... Alberti Magni e-corpus.