Cite the scanned version of the original dicionary like this:
Bosworth, Joseph. "endung." An Anglo-Saxon Dictionary: Based on the Manuscript Collections of the Late Joseph Bosworth. Ed. Thomas Northcote Toller. Oxford: Clarendon Press, 1898. 251.
.Add :-- Swá hwæt swá þé on eáge byreð æfter tíde cymð seó endung (fulfilment), Lch. iii. 154, 22. Neár worulde endunge, Past. 213, 6. On endungce in consummatione, Ps. L. 58, 14. On heora endunge þonne hié endiaþ, Bt. 16, 3; F. 56, 26. From endung a perfeccione, Lk. p. 2, 15. Æt þæs godspelles endunge qua perlecta, R. Ben. 35, 21.