What was the address of the Center for Retarded Adults at Beekman University in Flowers for Algernon?

Charlie studied at the Center for Retarded Adults, a special program in Beekman University in New York City. His journey to the University begins at work at the bakery. He asks his coworker, Joe Carp, how Joe learned to read, because Charlie wanted to learn too. Joe laughed, but a kind co-worker of Charlie's, Fanny Birden, told him about the Center for Retarded Adults, which she had heard about from her cousin who studied at...

Charlie studied at the Center for Retarded Adults, a special program in Beekman University in New York City. His journey to the University begins at work at the bakery. He asks his coworker, Joe Carp, how Joe learned to read, because Charlie wanted to learn too. Joe laughed, but a kind co-worker of Charlie's, Fanny Birden, told him about the Center for Retarded Adults, which she had heard about from her cousin who studied at Beekman. This is an instance where Charlie shows extraordinary initiative and a thirst for learning, which is a theme in his personality throughout the book. 

Charlie went to the University and by chance the first person he approached was Miss Kinian, who taught at the Center for Retarded Adults. She tells him to register and that she will teach him how to read. We find out the address of the building much later on in the story, when Charlie returns to the Center post-surgery. He is changed; he is now very intelligent and has gained social skills. 

June 6 - I had not been back to the Center for Retarded Adults since the operation,
and the thought of seeing the place was exciting. It's on Twenty-third
Street, east of Fifth Avenue, in an old schoolhouse that has been used by the
Beekman University Clinic for the last five years as a center for experimental education--special classes for the handicapped. The sign outside
on the doorway, framed by the old spiked gateway, is just a gleaming brass plate that says C. R. A. Beekman Extension.

The first time he enters the University and the second show a huge contrast between his abilities and behavior then and now.