Roy Chapman Andrews was not only an intrepid explorer and palaeontologist, but also a gifted promoter. The Central Asiatic Expeditions were accompanied by cameras to document the entire work. As the conditions were most time prohibitive - relief from the burning sun was given only by frequent sandstorms - many scenes showing the discovery and excavation of fossils were probably staged after the real work was done.
Many pictures of the expedition-photographer John B. Shackelford show the famous dinosaur nests filled with "Protoceratops" eggs (in fact Oviraptor eggs) superbly preserved. It seems unlikely that the eggs were in such good shape when first discovered. More strange is the common notion in popular culture that the nests contained exactly a dozen eggs, maybe this misconception was influenced by later published photos of the reconstructed nests.
In fact in Andrews's original descriptions the number of eggs per nests varies, from three to nine, only in one case he mentions thirteen eggs, however embedded in a block of sediment.
Fig.1. Original 1923 picture of (less than twelve) dinosaur eggs found at the Flaming Cliffs, from ANDREWS, R.C. ed. (1932): The New Conquest of Central Asia – A narrative of the explorations of the Central Asiatic Expeditions in Mongolia and China, 1921-1930 (image in public domain).
DAVIDSON, J.P. (2008): A History of Paleontology Illustration. Indian University Press, Bloomington: 217