Redirect Notice
 The previous page is sending you to https://www.sciencedirect.com/science/article/pii/S0007153687800712/pdf?md5=a0d1b380bcbd2956d10a2fd8fd133614&pid=1-s2.0-S0007153687800712-main.pdf.

 If you do not want to visit that page, you can return to the previous page.