Section 49 Extension of cooperative work to Puerto Rico
Section 50 Survey's share of cost of topographic mapping or water resources investigations carried on with States
Section 50-1 Funds for mappings and investigations considered intragovernmental funds
Section 50A Working capital fund for United States Geological Survey
Section 50B Recording of obligations against accounts receivable and crediting of amounts received; work involving cooperation with State, Territory, etc.
Section 50C Payment of costs incidental to utilization of services of volunteers
Section 50D Services of students or recent graduates