Woodcut illustration of the so-called Key of Saint Servatius (9th c.) in the Treasury of the Basilica of Saint Servatius in Maastricht, the Netherlands. One of 66 illustrations in Bock &amp; Willemsen's 1872 publication on the church treasures of St. Servatius and Our Lady, both in Maastricht.
M.A. Lambris &amp; M.R. Brend'amour, 1872 (woodcut)
<p>Franz Bock &amp; Michaël Willemsen (1872): <i>Die mittelalterlichen Kunst- und Reliquienschätze zu Maestricht, aufbewahrt in den ehemaligen Stiftskirchen des h. Servatius und Unserer Lieben Frau daselbst, usw.</i> L. Schwann, Keulen/Neuss
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