Sonntag, August. <br/><br/>
Observations on terrestrial magnetism in Mexico.  Conducted under the direction of Baron von Müller, with notes and illustrations of an examination of the volcano Popocatepetl and its vicinity. 
By August Sonntag. 
 - [Washington,  Smithsonian Institution,  1860] 
 - 4 p. l., 84 p.  front. (map) illus.  33 cm. 
 - Smithsonian contributions to knowledge. [vol. XI, art. 7] Smithsonian Institution publication 114. .
<br/><br/><label>LCCN: </label>s  13000052  
<br/><br/><label>Subjects--Topical Terms: </label><br/>Geomagnetism--Mexico.
<br/><br/><label>Subjects--Geographic Terms: </label><br/>Popocatépetl (Mexico)
<br/><br/><label>LC Class. No.: </label>Q11  / .S68