@article{liu1986,
  author  = {Liu, Selim and Saleh, Farida},
  title   = {Finite Difference Method Applied to Digital Image Processing},
  journal = {Open Access Journal of Engineering Applications},
  year    = {1986},
  volume  = {10},
  number  = {1},
  pages   = {761-772},
  issn    = {3105-7004},
  doi     = {10.55555/oajea.1986.1001.037},
  url     = {https://journal.bsaps.com/article/6304}
}