Louis Essen, Jack V. L. Parry: An atomic standard of frequency and time interval: A Cæsium Resonator. In: Nature. Band 176, Nr. 4476, 1955, S. 280–282, doi:10.1038/176280a0.
Louis Essen: Proposed new value for the velocity of light. In: Nature. Band 167, Nr. 4242, 1951, S. 258–259, doi:10.1038/167258a0.
Louis Essen: A new æther-drift experiment. In: Nature. Band 175, Nr. 4462, 1955, S. 793–794, doi:10.1038/175793a0.
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Louis Essen: Relativity – joke or swindle? In: Electronics & Wireless World. Band 94, 1988, S. 126–127.