<html><head></head><body><div style="color:#000; background-color:#fff; font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, Sans-Serif;font-size:16px"><div id="yui_3_16_0_1_1445400557621_6853">Dear Prof. Blaha,</div><div id="yui_3_16_0_1_1445400557621_6853">I know that but i need to know background of elastic-constants equations under pressure.</div><div id="yui_3_16_0_1_1445400557621_6853">As i wrote in my previous email i would like to know how i must correct these equations under pressure.</div><div id="yui_3_16_0_1_1445400557621_6853">Sincerely,</div><div id="yui_3_16_0_1_1445400557621_6853">Amir</div></div></body></html>