heat capacity, Math - title

https://dx.doi.org/10.1351/goldbook.H02753
Heat brought to a system to increase its temperature divided by that temperature increase. At constant volume Math - ei at constant pressure Math - ei, where Math - text is the internal energy and Math - text the enthalpy of the system.
Source:
PAC, 1996, 68, 957 (Glossary of terms in quantities and units in Clinical Chemistry (IUPAC-IFCC Recommendations 1996)) on page 975