The Russian equivalent of John Doe (or Joe Bloggs), <a href="https://en.wikipedia.org/wiki/Ivan_Ivanovich_(Vostok_programme)" class="extiw" title="en:Ivan Ivanovich (Vostok programme)">Ivan Ivanovich</a> was a model used to test Gagarin's pressure suit. They wrote 'model' on the forehead in case anyone found him and thought him a dead astronaut.
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