JSTOR Ref
C.R. Dodwell Lectionarium Sancti Lamberti Leodiensis Tempore Stephani Episcopi Paratum (901-920). Umbrae Codicum Occidentalium, Volume 8, by François Masai, Léon Gilissen 34.3 (1965), 235-236 DOI:10.2307/43627204
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