| Dar El Fikr for Printing publishing and distribution S | |
|---|---|
| Charlene Crabb, "Frankincense", Discover, January 1993• Maugh II, "Ubar, Fabled Lost City, Found by LA Team", The Los Angeles Times, 5 February 1992 | Joachim Chwaszcza, Yemen, 4PA Press, 1992• Maugh II, "Ubar, Fabled Lost City, Found by LA Team", The Los Angeles Times, 5 February 1992 |
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