A trichromatic test for spheric and astigmatic refraction

Daviess, P. A critical analysis of bichromatic tests used in clinical refraction of the eye.Brit. J. Phys. Opt. 14: 170–182 (1957).

Dobson, M. The application of the duochrome principle to the Maddox ‘V’ test for astigmatism.Trans. Ophthal. Soc. U.K. 48: 374–375 (1928).

Frey, R.G. Die Chromasie des Auges im Dienste der Refraktionsbestimmung.Klin. Mbl. Augenheilk. 129: 534–543 (1956).

Jacobs, M. The Brown duochrome refraction test.Amer. J. Ophthalm. 15: 313–319 (1932).

Stepanik, J. Der Duochrom-Sterntest.Ophthalmologica 131: 194–198 (1956).