Cite the scanned version of the original dicionary like this:
Toller, T. Northcote, and Joseph Bosworth. "un-fére." An Anglo-Saxon Dictionary: Based on the Manuscript Collections of the Late Joseph Bosworth : Supplement. Oxford: Clarendon Press, 1921. 734.
;adj. Incapacitated, disabled, infirm, feeble :-- Se wæs Æþelstánes biscopes gespelia syððan hé unfére wæs, Chr. 1055; Erl. 190, 21. [Þa iwærð þe king unfere. Swa þe king seoc læi ... ne mihte he þer of beon hæl, Laym. 6780. Al unfer he it (Moses's leprous hand) fond, Gen. and Ex. 2810. Þat licour for to dele unto þe unfere, L. H. R. 115, 277. See also Halliwell's Dict. Icel. ú-fœrr disabled.]