[1] A. S. Besicovitch:
Concentrated and rarified sets of points. Acta Math. Stock. 62 (1934), 289-300.
MR 1555386 |
Zbl 0009.10504
[4] S. H. Hechler:
On the existence of certain cofinal subsets of $^\omega \omega$. to appear in Axiomatic Set Theory, Proceedings of Symposia in Pure Mathematics 13 pt. 2, ed. T. J. Jech, American Mathematical Society, Providence, Rhode Island.
MR 0360266
[5] T. J. Jech:
Lectures in set-theory with particular emphasis on the method of forcing. Lect. Notes Math. 217, Springer-Verlag, Berlin 1971.
MR 0321738 |
Zbl 0236.02048
[7] F. Rothberger:
Sur les familles indénombrables de suites de nombres naturelles et les problèmes concernant la propriété C. Proc. Cam. Phil. Soc. 37 (1941), 109-126.
MR 0004281
[11] R. С. Solomon: Ultrafilters and ultraproducts. Ph. D. Thesis, London 1972.