@inbook{inbooka20bc9df,
title   = {A method for image background filtering of colored images using elliptical coordinates},
author = {Bonventi Júnior, Waldemar and Albuquerque, Antonio Roberto Pereira Leite de and Isotani, Sadao},
year = {1994},
publisher = {Elsevier},
journal   = {Optical Methods in Biomedical and Environmental Sciences}
}