My paper, "Birth Spacing and Fertility in the Presence of Son Preference and Sex-Selective Abortions: India's Experience Over Four Decades," is now in line for publication in Demography. The likely publication date is December 2021. Until then, you can find the final version here, together with the online appendix, and the GitHub repository with the paper and code (note, you will have to get the data yourself from DHS).