Ritter A, Mellor R, Chalmers J, Sunderland M, Lancaster K. Key considerations in planning for substance use treatment: estimating treatment need and demand. J Stud Alcohol Suppl. 2019 Jan;Supp1 18:22-30. doi: 10.15288/jsads.2019.s18.22
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.