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Die neu geregelte Alters- und Reliktenversorgung der Eisenbahnarbeiter in Preußen, Bayern und Elsaß-Lothringen
Oldenberg, K., (1889)
Keeping the railroad retirement program on track : government and railroads schould clarify roles and responsabilities
(1981)
The early pension plans of the Baltimore and Ohio and the Pennsylvania railroads, 1880-1937
Higgins, Neal Owen, (1974)