TY - RPRT TI - Subsurface Supergranular Vertical Flows as Measured Using Large Distance Separations in Time-Distance Helioseismology AU - Duvall, T. L., Jr. AU - Hanasoge, S. M. PY - 2012 UR - https://ntrs.nasa.gov/citations/20120009700 ID - 20120009700 ER -