Just to add a reference, an analysis of the polaritons in non cubic crystals can be found in this article.<div><br clear="all"><p style="margin: 0.0px 0.0px 0.0px 0.0px; font: 10.0px Helvetica"><span class="Apple-style-span" style="font-size: small;">R. Loudon, Advances</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">in</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">Physics,</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">2001,</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">Vol.</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">50,</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">No.</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">7,</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">813-864</span></p>
<div><br></div><div><br></div><div><br></div><div><p style="margin: 0.0px 0.0px 0.0px 0.0px; font: 8.0px Helvetica"><span class="Apple-style-span" style="font-size: small;">This</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">articl</span><span class="Apple-style-span" style="font-size: small;">e</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">was</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">originall</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">y</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">published</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">in</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">Advances</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">in</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">Physics,</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">volume</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">13,</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">1964</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">.</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">It</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">attracted</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">114</span><span class="Apple-style-span" style="font-size: small;">7</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">citations</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">by</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">October</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">2001,</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">and</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">is</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">ranked</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">2</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">in</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">the</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">index</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">of</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">article</span><span class="Apple-style-span" style="font-size: small;">s</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">attracting</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">more</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">than</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">100</span><span style="font: 12.0px Helvetica"><span class="Apple-style-span" style="font-size: small;"> </span></span><span class="Apple-style-span" style="font-size: small;">citations.</span></p>
</div><div><br></div>-- <br><div><br></div>
<div><br></div>Eduardo Menendez<br>Departamento de Fisica<br>Facultad de Ciencias<br>Universidad de Chile<br>Phone: (56)(2)9787439<br>URL: <a href="http://fisica.ciencias.uchile.cl/~emenendez" target="_blank">http://fisica.ciencias.uchile.cl/~emenendez</a><br>

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