The Concentrated Range Extender with Gain. - James L. Henry; Kenneth E. Stiefel; Dale E. Stone; David H. Williamson (IEEE Trans. Commun., 1980)

The SLC 96 subscriber loop carrier system: Channel bank. - Michael M. Luniewicz; John W. Olson; Kenneth E. Stiefel (AT&T Bell Lab. Tech. J., 1984)