Moncho did you find API Std 11D3:2008, Progressing Cavity Pump Systems for Artificial Lift API RP 11V10:2008, Recommended Practices for Design and Operation of Intermittent and Chamber Gas-lift Wells and Systems. - 1st edition API TR 11L:2008, Design calculations for sucker rod pumping systems (Conventional units). - 5th edition. if you find it could you share please?