** install from github
net install gtfpch, from("https://raw.githubusercontent.com/kerrydu/gtfpch/master/") replace

**install from gitee
net install gtfpch, from(https://gitee.com/kerrydu/gtfpch/raw/master/) replace

@TechReport {WangDuZhang2021,
  Author = {Wang, D., Du, K., and Zhang, N.},
  Title = {Measuring technical efficiency and total factor productivity change with undesirable outputs in Stata},
  Note = {Stata Journal, forthcoming},
  Year = {2021},
}