Vickers AD, Palmer SCF. The influence of canopy cover and other factors upon regeneration of Scots pine and associated ground flora within Glen Tanar NNR. Forestry (Lond). 2000;73(1):37-49.
Rothman KJ, Glass RL, Espinal F, Velez H. Caries-free teeth in the absence of fluoride ion. J Public Health Dent. 1972;32(4):225-8. doi: 10.1111/j.1752-7325.1972.tb03977.x