Herbert Hellerman. On the Input Impedance Network Error in Operational Amplifiers. IEEE Transactions on Computers, 4(3):118, 1955. [doi]
@article{Hellerman55,
title = {On the Input Impedance Network Error in Operational Amplifiers},
author = {Herbert Hellerman},
year = {1955},
doi = {10.1109/IRETELC.1955.5407910},
url = {http://dx.doi.org/10.1109/IRETELC.1955.5407910},
researchr = {https://researchr.org/publication/Hellerman55},
cites = {0},
citedby = {0},
journal = {IEEE Transactions on Computers},
volume = {4},
number = {3},
pages = {118},
}