Cite the scanned version of the original dicionary like this:
Toller, T. Northcote, and Joseph Bosworth. "in-smoh." An Anglo-Saxon Dictionary: Based on the Manuscript Collections of the Late Joseph Bosworth : Supplement. Oxford: Clarendon Press, 1921. 594.
;gen. -smós [?]; m. A slough :-- Hé ágeaf ðone clǽnan gást and ðæs líchaman insmoh [exuvias] forlét monnum tó mundbyrde he gave up the clean spirit, and left the slough of the body as a protection for men, Shrn. 126, 2. v. smúgan ; and cf. O. Frs. in-smuge a creeping in.