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The non-regular dodecagons {(d,d,D,D)³} are shield dodecagons. Their vertex angles are alternatingly d = arccos[-sqrt(5/8)] = 142.238756° resp. D = arccos[-(3+sqrt(5))/sqrt(32)] = 157.761244°.

Incidence matrix

48  * |  1  1  1  0 | 1 1  1 [3,8,D]
 * 24 |  0  0  2  1 | 0 2  1 [3,d,d]
------+-------------+-------
 2  0 | 24  *  *  * | 1 0  1
 2  0 |  * 24  *  * | 1 1  0
 1  1 |  *  * 48  * | 0 1  1
 0  2 |  *  *  * 12 | 0 2  0
------+-------------+-------
 8  0 |  4  4  0  0 | 6 *  *
 6  6 |  0  3  6  3 | * 8  *  {(d,d,D,D)3}
 2  1 |  1  0  2  0 | * * 24