# Sh:458

- Abraham, U., & Shelah, S. (1996).
*Martin’s axiom and \Delta^2_1 well-ordering of the reals*. Arch. Math. Logic,**35**(5-6), 287–298. arXiv: math/9408214 DOI: 10.1007/s001530050046 MR: 1420259 -
Abstract:

Assuming an inaccessible cardinal \kappa, there is a generic extension in which MA + 2^{\aleph_0} = \kappa holds and the reals have a \Delta^2_1 well-ordering. - Version 1994-08-30_10 (16p) published version (12p)

Bib entry

@article{Sh:458, author = {Abraham, Uri and Shelah, Saharon}, title = {{Martin's axiom and $\Delta^2_1$ well-ordering of the reals}}, journal = {Arch. Math. Logic}, fjournal = {Archive for Mathematical Logic}, volume = {35}, number = {5-6}, year = {1996}, pages = {287--298}, issn = {0933-5846}, mrnumber = {1420259}, mrclass = {03E50 (03E15 03E35 03E40)}, doi = {10.1007/s001530050046}, note = {\href{https://arxiv.org/abs/math/9408214}{arXiv: math/9408214}}, arxiv_number = {math/9408214} }