BR is not on-line, so I've included a section from the conclusion. His starting point is Merce's early education in the theater (Cornish School, Seattle), which included exposure to Graham technique.
Later, as a young man, he reached New York and was invited by Graham to take class with her company. Eventually he performed with her company.
(I've cut out parts of this section, so it stays more or less within copyright guidelines.)
[ ... ]
Martha suggested that I study at the School of American Ballet. [ ...] She called up Lincoln Kirstein. I went to the school and was terrified because Lincoln was such a fierce person or thought he was. Lincoln said, "Well, what do you want to study? You're a modern dancer. What do you want?" O can still hear him shouting at me: "What do you want to study ballet for?" I said, "Well, I like all kinds of dancing." Which is true.
[ ... ] When I studied at the School of American Ballet, I couldn't go all the time. I was trying to learn something about ballet, which I knew I didn't know enough about. I began to read about it and find out its history. I read the letters of Noverre and a wonderful book by the Italian Carlo Blasis, with beautiful drawings of the classical positions.
I continued to dance with Martha.
[ ... ]
When I was ready to leave Martha and her company, I told her that I wanted to work on my own things. At that time there were not that many male modern dancers. Mostly they were in ballet. I knew that it would be difficult to replace me, so I told her I would stay another year to give her time to find someone.
[ ... ]
Coming to New York, that in itself was so interesting. The city struck me from the first day I was here. You turn a corner and find something exciting. With all the difficulties, New York remains colossal. You can have a far more pleasant day-to-day existence in London or Paris, but if you're attracted to New York, somehow you can't ait to come home.