http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
The Cushing Library Lit/Mitchell copies of no. 15, 20, and 24 are a donation from J. Lawrence Mitchell.
The Cushing Library Lit/Mitchell copy of no. 20 has 1 piece of ephemera; contains a supplement sheet to no. 20.
There is a photograph of Anna Akhmatova on the front cover of no. 20.