Cite the scanned version of the original dicionary like this:
Toller, T. Northcote, and Joseph Bosworth. "á-brecan." An Anglo-Saxon Dictionary: Based on the Manuscript Collections of the Late Joseph Bosworth : Supplement. Oxford: Clarendon Press, 1921. 755.
, ic -brece, ðu -bricst, he -bricþ; p. -bræc, pl. -brǽcon; pp. -brocen To break, vanquish, to take by storm, to assault, destroy; frangere, effringere, expugnare :-- Abrecan ne meahton reced they might not break the house, Cd. 115; Th. 150, 14; Gen. 2491. He Babilone abrecan wolde he would destroy Babylon, Cd. 209; Th. 259, 10; Dan. 685. Hú ǽnig man mihte swylce burh abrecan how any man could take such a town, Ors. 2, 4; Bos. 44, 16. DER. brecan.