RT Journal Article SR Electronic T1 A Trial of the Direct Method for Determining the Tensions of O2 and CO2 in Blood JF Thorax JO Thorax FD BMJ Publishing Group Ltd and British Thoracic Society SP 251 OP 253 DO 10.1136/thx.14.3.251 VO 14 IS 3 A1 Semple, S. J. G. A1 Young, I. Maureen YR 1959 UL http://thorax.bmj.com/content/14/3/251.abstract AB