T. W. Butler. SPATIAL STATISTICS AND ANALYSIS OF EARTH'S IONOSPHERE. Ph.D. Thesis, Boston University,  2013 .

H. Dahlgren, J. L. Semeter, K. Hosokawa, M. J. Nicolls, T. W. Butler, M. G. Johnsen, K. Shiokawa, and C. Heinselman. Direct three-dimensional imaging of polar ionospheric structures with the Resolute Bay Incoherent Scatter Radar. Geophys. Res. Lett., volume 39,  2012 .

J. Semeter, T. W. Butler, M. Zettergren, C. J. Heinselman, and M. J. Nicolls. Composite imaging of auroral forms and convective flows during a substorm cycle. J. Geophys. Res., volume 115,  2010 .

T. W. Butler, J. Semeter, C. J. Heinselman, and M. J. Nicolls. Imaging F region drifts using monostatic phased-array incoherent scatter radar. Radio Sci., volume 45,  2010 .

J. Semeter, T. Butler, C. Heinselman, M. Nicolls, J. Kelly, and D. Hampton. Volumetric imaging of the auroral ionosphere: Initial results from PFISR. J. Atmos Solar-Terr. Phys., volume 71, issue 6, pages 738-743,  2009 .