TY - GEN AU - Robert E Berger C2 - , National Institute of Standards and Technology, Gaithersburg, MD DA - 1980-01-01 05:01:00 DO - https://doi.org/10.6028/NBS.IR.80-1987 LA - en PB - , National Institute of Standards and Technology, Gaithersburg, MD PY - 1980 TI - A mathematical model for use in evaluating and developing impact test methods for protective headgear: ER -