Array (1994). Foreword to The Guide to Larry Niven's Ringworld.

Array (1993). Introduction to Bridging the Galaxies.

Array (1991). Introduction to Man-Kzin Wars IV.

Array (1989). Introduction to Man-Kzin Wars II.

Array (1988). Sideways in Time, an introduction to Ward Moore's Bring the Jubilee.

Array (1988). Introduction to Man-Kzin Wars I.

Array (1985). Introduction.

Array (1981). Introduction.

Array (1980). Introduction: The Known Space Series.

Array (1980). Memoir.

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