I have been looking into the history of programming, and everybody and their grandmothers begin the subject with a claim more or less similar to the following:
At first, programmers used machine code. Later, there were assemblers. Then, pseudo code, and finally Fortran came.
With some Google-fu I can very easily find examples of punch cards containing Fortran statements, COBOL statements, and some Assembly statements. Wikipedia has some punch card examples for short code.
But I am yet to find a reliable source explaining how programmers entered machine code into computers using punch cards. Or pseudo code using punch cards.
Were there really punch cards for machine code? Or when stored programs appeared they were already programmable with Assembly?