API SPEC 6A-2018 Specification for Wellhead and Tree Equipment (TWENTY-FIRST EDITION; API Monogram p API 19C-2018 Measurement of and Specifications for Proppants Used in Hydraulic Fracturing and Gravel API TR 17TR8-2018 High-pressure High-temperature Design Guidelines (SECOND EDITION; ERTA 1_ March 20 API RP 578-2018 Guidelines for a Material Verification Program (MVP) for New and Existing Assets (Th API SPEC 17L1-2021 Specification for Ancillary Equipment for Flexible Pipes and Subsea Umbilicals - API RP 17L2 -2021 Recommended Practice for Ancillary Equipment for Flexible Pipes and Subsea Umbilic API RP 1115-2018 Design and Operation of Solution-mined Salt Caverns Used for Liquid Hydrocarbon Sto API TR 2577-2018 Performance of Full-bore Vortex Meters for Measurement of Liquid Flows