This series was published in the 1960s under a grant from the Office of Naval Research as 105 pamphlets. The pamphlets were then grouped by subject and republished under a grant from the National Science Foundation. For titles of papers in the eleven volumes of this series, refer to the AMS publication Index to Translations Selected by the American Mathematical Society. No further volumes will be published in this series, however, back volumes are available. (ISSN 0065-9290) Hardcover; reprints in softcover.