The Crinoidea flexibilia /
Springer, Frank
The Crinoidea flexibilia / by Frank Springer. - City of Washington : Smithsonian institution, 1920. - 2 v. : ill. ; 33 cm.
The Crinoidea flexibilia / by Frank Springer. - City of Washington : Smithsonian institution, 1920. - 2 v. : ill. ; 33 cm.