Fixed Payment Medical Service in the Lumber and Mining Industries of Washington, Oregon and California

Pierce Williams, The Purchase of Medical Care through Fixed Periodic Payment (NBER, 1932), chap. 3, https://www.nber.org/books-and-chapters/purchase-medical-care-through-fixed-periodic-payment/fixed-payment-medical-service-lumber-and-mining-industries-washington-oregon-and-california.