@article{McMahon2019, author = "Glenda McMahon and Ken Chatterton", title = "{Sanitary seal for a borehole}", year = "2019", month = "4", url = "https://repository.lboro.ac.uk/articles/figure/Sanitary_seal_for_a_borehole/7982648", doi = "10.17028/rd.lboro.7982648.v1" }