APA

Turner J. R. G., Sheppard P. M., .Absence of crossing-over in female butterflies (<Heliconius>). : .

Chicago

Turner John R G, Sheppard P M, .Absence of crossing-over in female butterflies (<Heliconius>). : .

Harvard

Turner J. R. G., Sheppard P. M., .Absence of crossing-over in female butterflies (<Heliconius>). : .

MLA

Turner John R G, Sheppard P M, .: . .