First appear of the USRP blocks in GNU Radio

Hi community!

I'm Isaac. I'd like to ask you a question. I'd like to add in my thesis information about the first time the USRP blocks appeared and were used. I found that the USRP1 was designed in 2004 but I'm not sure if this USRP appeared with the blocks or not.

https://www.sgo.fi/~j/usrp/overview-open.pdf

If you know any information about it , I would really appreciate it.

Thanks

Regards

Isaac T.