RoseH. J.Jr.ChristianR. P.LindsayJ. R., and LarsonR. R., U. S. Geol. Survey Prof. Paper650B, B128 (1969).
2.
EvansH. T.Jr., in Proceedings of the Apollo 11 Lunar Science Conference, edited by LevinsonA. A. (Pergamon, New York, 1970), Vol. 1, p. 399.
3.
DenceM. R.DouglasJ. A. V.PlantA. G., and TraillR. J., in Ref. 2, p. 315.
4.
KeilK.BunchT. E., and PrinzM., in Ref. 2, p. 561.
5.
BrownG. M.EmeleusC. H.HollandJ. G., and PhillipsR., in Ref. 2, p. 195.
6.
El GoresyA.RamdohrP., and TaylorL. A., in Proceedings of the Second Lunar Science Conference, edited by LevinsonA. A. (M.I.T. Press, Cambridge, Mass., 1971), Vol. 1, p. 219.
7.
CameronE. N., in Ref. 6, p. 193.
8.
GibbF. G. F.StumpflE. F., and ZussmanJ., Earth Planet. Sci. Lett.9, 217 (1970).
9.
ChampnessP. E.DunhamA. C.GibbF. G. F.GilesH. N.MacKenzieW. S.StumpflE. F., and ZussmanJ., in Ref. 6, p. 359.