Hills and Nakamura had a vision of feeding the world from lakes, seas and backyard aquaculture and in 1975 they authored a book, Food from Sunlight which published all their proprietary research as open source for the world to use in the cause against global famine and malnutrition.
For millennia spirulina had been a food staple for natives of Lake Chad and also for the Aztecs but Hills funded much of the early experimentation needed for its successful modern day mass cultivation, described in Dr Nakamura's book Spirulina: Food for a Hungry World [REF].