Critical field/temperature plots for HTSCs

[Zymandia]

Hi Guys,
A while back I saw a plot of Bc against Tc for a cuprate sample. There seemed to be a distinct kink in the curve in the 10-15K region.
I'd like to see a few plots of optimally doped (or there abouts) cuprates particularly the <40K region. My inept Google searching only gets me the cuprate phase-diagram of SC by doping :(
Not being an academic, I can't always open papers I'm pointed at.
Thanks in advance for any help.

 

[nbo10]

I'm not sure how many optimally doped cuprates have a Tc less than 40K.

 

[Zymandia]

None I hope! I'm looking for accurate measured Bc against Tc for samples of Tc > 100K.
I saw a set of 3 diagrams for 3 different cuprates and each had this feature at < 20K, but I haven't been able to find them again and I can't afford to buy papers with likely abstracts/titles.
Any links gratefully appreciated.