Stefan Pogorzalek, Kirill G. Fedorov, Ling Zhong, Jan Goetz, Friedrich Wulschner, Michael Fischer, Peter Eder, Edwar Xie, Kunihiro Inomata, Tsuyoshi Yamamoto, Yasunobu Nakamura, Achim Marx, Frank Deppe, Rudolf Gross: Hysteretic Flux Response and Nondegenerate Gain of Flux-Driven Josephson Parametric Amplifiers. American Physical Society 2017Phys. Rev. Applied: 8. https://link.aps.org/doi/10.1103/PhysRevApplied.8.024012