A 2018 paper by Strang about this approach: https://www.tandfonline.com/doi/abs/10.1080/00029890.2018.1408378 https://www.tandfonline.com/doi/abs/10.1080/00029

A 2018 paper by Strang about this approach: https://www.tandfonline.com/doi/abs/10.1080/00029890.2018.1408378 https://www.tandfonline.com/doi/abs/10.1080/00029890.2018.14...