Cite the scanned version of the original dicionary like this:
Bosworth, Joseph. "láreów-líc." An Anglo-Saxon Dictionary: Based on the Manuscript Collections of the Late Joseph Bosworth. Ed. Thomas Northcote Toller. Oxford: Clarendon Press, 1898. 621.
.Add: of a teacher or master, having the character of a master :-- Þurh láréwlicum basincge magistri melote, An. Ox. 1471. On eallum þingum láreówlicum hí fylian regole in omnibus magistram sequantur regulam, R. Ben. 9. 18, 9.