Champion, H.G.2023-11-162023-11-161923Champion, H.G. (1923) An investigation of certain factors concerning the resin-tapping industry in Pinus longifolia. Indian Forest Bulletin . Superintendent Government Printing .https://frirepo.bestbookbuddies.com/handle/123456789/720enAn investigation of certain factors concerning the resin-tapping industry in Pinus longifoliaBook