erc: who: Graves, Ralph L. what: Northern Pacific (NP) 1624 when: 19460821 where: https://gateway.okhistory.org/ark:/67531/metadc2298648/ erc-support: who: University of North Texas Libraries what: Permanent: Stable Content: when: 20081203 where: https://gateway.okhistory.org/ark:/67531/