@article{L Harris2013, author = "A L Harris and K Morrison", title = "{Coordinate system for projectile-helium atom system}", year = "2013", month = "6", url = "https://iop.figshare.com/articles/figure/_Coordinate_system_for_projectile_helium_atom_system/1012142", doi = "10.6084/m9.figshare.1012142.v1" }