<html><head></head><body><div class="yahoo-style-wrap" style="font-family:Helvetica Neue, Helvetica, Arial, sans-serif;font-size:16px;"><div dir="ltr" data-setdir="false">Hi all,</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">any update for my question? </div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">While waiting for a reply a kept searching for additional material that could help me understand</div><div dir="ltr" data-setdir="false">why A1 and A2 are added to the formulation but I'm still stuck...</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">Regards,</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">Marco</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false"><br></div></div></body></html>