This a model from the article:
Modelling sarcoplasmic reticulum calcium ATPase and its regulation in cardiac
myocytes.
Koivumaki JT, Takalo J, Korhonen T, Tavi P, Weckstrom M. Philos Transact A Math Phys Eng Sci
2009 Jun 13;367(1896):2181-202 1941...