References for the Particle Field Interaction, Nonrelativistic Interface
1. C.D. Child, “Discharge from hot CaO,” Phys. Rev. (Series I), vol. 32, no. 5, pp. 492–511, 1911.
2. S. Humphries, “Numerical modeling of space-charge-limited charged-particle emission on a conformal triangular mesh,” J. Comput. Phys., vol. 25, no. 2, pp. 488–497, 1996.