PAC, 1984, 56, 567
(Physicochemical quantities and units in clinical chemistry with special emphasis on activities and activity coefficients (Recommendations 1983))
on page 569
Transformed and rewritten from PDF version (entry
http://www.iupac.org/goldbook/B00617.pdf)
by: Miloslav Nic, Jiri Jirat, Bedrich Kosata, ICT Prague, Czech Republic