VLBI for Gravity Probe B: the guide star, IM PegasiDOI: info:10.1088/0264-9381/32/22/224021v. 32224021
Bartel, N., Bietenholz, M. F., Lebach, D. E., Ransom, R. R., Ratner, M. I., and Shapiro, Irwin I. 2015. "VLBI for Gravity Probe B: the guide star, IM Pegasi." Classical and Quantum Gravity, 32 224021. https://doi.org/10.1088/0264-9381/32/22/224021.