@article{GENERAL,
      recid = {9231},
      title = {Practical Helicopter Design},
      journal = {Journal of Naval Engineering},
      address = {1975},
      number = {GENERAL},
      abstract = {Practical Helicopter Design.
December 1975.
COMMANDER M.  F. SIMPSON, C.ENG., M.I.MECH.E., M.R.AE.S., R.N.},
      url = {http://library.imarest.org/record/9231},
}