TY - GEN AU - Hill, David C2 - Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD DA - 1984-09-01 LA - en PB - Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD PY - 1984 TI - Radio Propagation in a Coal Seam and the Inverse Problem ER -