Envoy to New Worlds / Flight from Yesterday

SCIENCE FICTION-2 BOOKS IN ONE VOLUME-ENVOY TO NEW WORLDS,K.LAUMER,THE AUTHORISED HISTORY OF THE FRONTIER WORLDS OF THE 29TH CENTURY DOES NOT INCLUDE THE SIGNIFICANT WORK DONE BY CERTAIN CAREER DIPLOMATS LIKE JAME RETIEF,IN HIS EFFORTS TO ALLEVIATE STRIFE IN CERTAIN PARTS OF THE EMERGING GALAXY.FLIGHT FROM YESTERDAY BY ROBERT MOORE WILLIAMS/IS A WONDER WEBWORK OF TIME AND SPACE.