Inter- and intra-observer reliability and agreement of O2Pulse inflection during cardiopulmonary exercise testing: A comparison of subjective and novel objective methodology. oleh Thomas Nickolay, Gordon McGregor, Richard Powell, Brian Begg, Stefan Birkett, Simon Nichols, Stuart Ennis, Prithwish Banerjee, Rob Shave, James Metcalfe, Angela Hoye, Lee Ingle