text: *The solar constant and the solar spectrum measured from a research aircraft, edited by Matthew P. Thekaekara. Solar energy. Spectrum, Solar. Aeronautics in astronomy.
  *Thoughts twice dyed : reprinted from the series of "One minute meditation" / by Matthew P. Thekaekara, S.J 
  *"The Extraterrestrial Solar Spectrum" A.J Drummond and M.P. Thekaekara, Eds. Institute of Environmental Sciences, Mount Prospect Illinois, 1973.