Zhu, Y., Y. Chen, Z. Lu, S. Pan, G.-R. Xue, Y. Yu, and Q. Yang. “Heterogeneous Transfer Learning for Image Classification”. Proceedings of the AAAI Conference on Artificial Intelligence, vol. 25, no. 1, Aug. 2011, pp. 1304-9, doi:10.1609/aaai.v25i1.8090.