* Howard, I. K. (2002). «H Is for Enthalpy, Thanks to Heike Kamerlingh Onnes and Alfred W. Porter». J. Chem. Educ. 79 (6): 697-698 | * Howard, I. K. (2002). «H Is for Enthalpy, Thanks to Heike Kamerlingh Onnes and Alfred W. Porter». J. Chem. Educ. 79 (6): 697-698 |