Cite the scanned version of the original dicionary like this:
Bosworth, Joseph. "hæg-steald." An Anglo-Saxon Dictionary: Based on the Manuscript Collections of the Late Joseph Bosworth. Ed. Thomas Northcote Toller. Oxford: Clarendon Press, 1898. 499.
.Add; a tiro, novice :-- Warna ǽr cniht beón þænne hægesteald ł geong cempa caue ante miles esse quam tiro, Scint. 205, 9. Sé ðe hehstald (uirgo) gecoren is . . . þ̵te ðá hehstald hehstald gehealde (ut uirginem uirgo seruarei), Jn. p. l, 2-5. Ðǽr hehstalde uirgini, 2, 4. Of heghstald ex uirgine. Mt. p. 13, 2. Swylce geongum hægstealde, rince, hysse ut effebo hircitallo, An. Ox. 3476. Ðerh þ̵ hehstald per uirginem, Jn. p. i. 13. Alle hehstalde ðá ilco, Mt. 25, 7. Hehstaldo, ii.