Cite the scanned version of the original dicionary like this:
Toller, T. Northcote, and Joseph Bosworth. "flówan." An Anglo-Saxon Dictionary: Based on the Manuscript Collections of the Late Joseph Bosworth : Supplement. Oxford: Clarendon Press, 1921. 764.
;part. flówende; ic flówe, ðu flówest, fléwst, he flóweþ, flewþ, pl. flowaþ; p. fleów, pl. fleówon; pp. flówen To FLOW, issue; fluĕre, fluctuāre, inundāre :-- Ðæt ealle eán eft flówan mágon that all waters may flow again, Boutr. Scrd. 21, 16. Flówan mót ýþ ofer eall lond the wave may flow over all the land, Salm. Kmbl. 644; Sal. 321: Ps. Th. 77, 21: 104, 36: Menol. Fox 555; Gn. C. 47. Com flówende flód the flood came flowing, Byrht. Th. 133, 44; By. 65. Ic flówe fluo, Ælfc. Gr. 28, 5; Som. 32, 4.