1. Barjatya, A., Swenson, C.M., Thompson, D.C., and Wright, K.H., Jr., Invited article: Data analysis of the floating potential measurement unit aboard the international space station, Rev. Sci. Instrum., 2009, nos. 1–11, pp. 80, 041301.
2. Brace, L.H., Spencer, N.W., and Dalgarno, A., Detailed behaviour of the mid-latitude ionosphere from the Explorer XVII satellite, Planet. Space Sci., 1965, vol. 13, no. 7, pp. 647–666.
3. Brace, L.H. Langmuir probe measurements in the ionosphere, in Measurement Techniques in Space Plasmas: Particles, Pfaff, R.F., Borovsky, J.E., and Young, D.T., Eds., Washington, D.C.: American Geophysical Union, 1998, pp. 23–35.
4. Georgieva, K. and Kirov, B., Influence of pollution and coating on the accuracy of Langmuir probe measurements of electronic temperature, Bulg. Geofiz. Spis., 1983, vol. 9, no. 1, pp. 71–77.
5. Georgieva, K., Kirov, B., Kraleva, L., The accuracy of ion parameters measured by a cylindrical Langmuir probe, C. R. Acad. Bulg. Sci., 1984, vol. 37, no. 2, p. 157.