XuGuo，Yan  Wang，Niwen  Zhou，Xuehu  Zhu. Optimal  weighted  two-sample  t-test  with  partially  paired  data  in  a  unified  framework.

Journal of Applied Statistics, 2020,Online.

DOI: 10.1080/02664763.2020.1753027

https://www.tandfonline.com/doi/full/10.1080/02664763.2020.1753027