1. Ajelis, V., Björklund, A., Falck, B., Lindvall, O., Loren, I. and Walles, B.: Application of the aluminum-formaldehyde (ALFA) histofluorescence method for demonstration of peripheral stores of catecholamines and indolamines in freeze-dried paraffin-embedded tissue, cryostat sections and whole-mounts. Histochemistry 65; 1-15, 1979.
2. Corrodi, H., Hillarp, N.-A. and Jonsson, G.: Fluorescence methods for the histochemical demonstration of monoamines. Sodium borohydride reduction of the fluorescent compounds as a specificity test. J. Histochem. Cytochem. 12; 582-586, 1964.
3. Falck, B., Hillarp, N.-A., Thieme, G. and Torp, A.: Fluorescence of catecholamines and related compounds with formaldehyde. J. Histochem. Cytochem. 10; 348-354, 1962.
4. Furness, J. B., Costa, M. and Wilson, A. J.: Water-stable fluorophores, produced by reaction with aldehyde solutions, for the histochemical localization of catechol- and indolethylamines. Histochemistry 52; 159-170, 1977.
5. Fuxe, L., Hökfelt, T., Jonsson, G. and Ungerstedt, U.: Fluorescence microscopy in neuroanatomy. In Contemporary Research Methods in Neuroanatomy, ed. by W. J. H. Nauta and S. O. E. Ebbeson, Springer Verlag, Berlin, 1970, p. 275-314.