This particular skeleton was discovered in Mongolia in late 1940’s - early 1950’s. At the time USSR had organized a number of paleontological expeditions into the region - with great success. One of the most famous paleontologists of the expeditions was Ivan Antonovich Efremov (photo below), although he is better known as a science fiction writer, depicting a bright, socialist future of peaceful space exploration.
There’s a theory (AFAIK accepted one) that the crests were sound amplification devices for their calls
Oh
𝕨𝕖𝕝𝕝, 𝕕𝕠𝕟’𝕥 𝕀 𝕝𝕠𝕠𝕜 𝕤𝕚𝕝𝕝𝕪
No problem, friend