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Goncharov, S. S.,
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Remmel, J. B. and
Marek, Wictor W., eds. 1998a.
Handbook of Recursive Mathematics, volume 1: Recursive Model Theory.
Studies in Logic and the Foundations of Mathematics n. 138. Amsterdam: North-Holland Publishing Co.
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Goncharov, S. S.,
Nerode, Anil,
Remmel, J. B. and
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Handbook of Recursive Mathematics, volume 2: Recursive Algebra, Analysis and Combinatorics.
Studies in Logic and the Foundations of Mathematics n. 139. Amsterdam: North-Holland Publishing Co.