共 8 条
[1]
Brown RW., 1962, US GEOL SURV PROF PA, V375, P1
[2]
HEWITSON W, 1962, ANN MISSOURI BOT GAR, V48, P57
[3]
MILLER CN, 1971, CONTRIB MUS PALEONTO, V28, P105
[4]
Miller CN, 1967, CONTRIB MUS PALEONTO, V21, P139
[5]
ROEHLER HW, 1979, US GEOL SURV PROF A, V1065, pA1
[6]
TIDWELL W D, 1986, SIDA Contributions to Botany, V11, P401
[7]
TIDWELL WD, 1976, B YOUNG U GEOL STUD, V22, P77
[8]
WINTERFELD G F, 1982, Contributions to Geology University of Wyoming, V21, P73