Not sure if this is what you're looking for, but this publication may help:

Kwei G H, Lawson A C, Billinge S J L, Cheong S W, 

Journal of Physical Chemistry 97 (1993) 2368-2377,  

Structures of the ferroelectric phases of barium titanate

It provides crystallographic data from 15K to 270K.

Also see:

Xiao C J, Jin C Q, Wang X H, 

Materials Chemistry and Physics 111 (2008) 209-212, 

Crystal structure of dense nanocrystalline BaTiO3 ceramics 

Shirane G, Danner H, Pepinsky R, 

Physical Review 105 (1957) 856-860, 

Neutron diffraction study of orthorhombic BaTiO3

Additionally, this website may provide additional information:

http://rruff.geo.arizona.edu/AMS/amcsd.php

Thank you very much for the message.

Regards,

Agnieszka Szuster-Janiaczyk

Thank you Mr. Kirk G Scheckel, I will have a look on the papers suggested by you.