According to the OpenCV documentation, the DisparityBilateralFilter is based on the following paper:
Q. Yang, L. Wang, and N. Ahuja. A constant-space belief propagation algorithm for stereo matching. In CVPR, 2010. [pdf]
But I am reading that paper, and I don't see anywhere where bilateral filters are mentioned. I'll admit that it's a bit over my head.
I don't quite understand what the source code is doing for that class, but could they maybe have meant to cite this paper (or one of Yang's other papers on bilateral filters?):
Qingxiong Yang, Kar-Han Tan and Narendra Ahuja, Real-time O(1) Bilateral Filtering, IEEE Conference on Computer Vision and Pattern Recognition (CVPR) 2009. [pdf2]
Can anybody confirm which paper the DisparityBilateralFilter is based on?