This series is published for the Institute of Mathematical Statistics by the American Mathematical Society. Individual members of IMS may order at the individual member price. For titles of papers in volumes 1 through 13 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. (LC 61-9803) (ISSN 0065-9274) Hardcover; reprints in softcover.