%0 Journal Article %A J M Rattenbury %T Principles and Applications of Laboratory Instrumentation %D 1990 %R 10.1136/jcp.43.6.521-e %J Journal of Clinical Pathology %P 521-522 %V 43 %N 6 %U https://jcp.bmj.com/content/jclinpath/43/6/521.5.full.pdf