1 Buck, A.L. (1981). New equations for computing vapor pressure and enhancement factor. J. Appl. Meteor. 20:1527-1532.
2 Escribano-Rocafort, A.G., Ventre-Lespiaucq, A.B., Granado-Yela, C., L pez-Pintor, A., Delgado, J.A., Mu oz, V., Dorado, G.A. and Balaguer, L. (2014), Simplifying data acquisition in plant canopies- Measurements of leaf angles with a cell phone. Methods Ecol Evol, 5: 132-140.
3 Genty, B., Wonders, J. & Baker, N.R., 1990. Non-photochemical quenching of Fo in leaves is emission wavelength dependent: consequences for quenching analysis and its interpretation. Photosynthesis Research, 26(2), pp.133–139.
4 Iqbal, M. “An Introduction to Solar Radiation”. New York: 1983; pp. 23-25. (Chapter 1, Google Books).
5 Loriaux SD, et al. (2013). Closing in on maximum yield of chlorophyll fluorescence using a single multiphase flash of sub-saturating intensity. Plant Cell Environ. 36:1755-1770.
6 Michalsky, J. J. “The Astronomical Almanac’s Algorithm for Approximate Solar Position(1950-2050)”. Solar Energy. Vol. 40, No. 3, 1988; pp. 227-235, USA.
7 Pfündel, E.E. et al., 2013. Deriving fluorometer-specific values of relative PSI fluorescence intensity from quenching of F0 fluorescence in leaves of Arabidopsis thaliana and Zea mays. Photosynthesis research, 114(3), pp.189–206.
8 Reda, I.; Andreas, A., Solar Position Algorithm for Solar Radiation Applications, Solar Energy. Vol. 76(5),v2004; pp. 577-589) See also C code and a web calculator here: