# LeNet > [Backpropagation Applied to Handwritten Zip Code Recognition](https://ieeexplore.ieee.org/document/6795724) ## Abstract The ability of learning networks to generalize can be greatly enhanced by providing constraints from the task domain. This paper demonstrates how such constraints can be integrated into a backpropagation network through the architecture of the network. This approach has been successfully applied to the recognition of handwritten zip code digits provided by the U.S. Postal Service. A single network learns the entire recognition operation, going from the normalized image of the character to the final classification.
## Citation ``` @ARTICLE{6795724, author={Y. {LeCun} and B. {Boser} and J. S. {Denker} and D. {Henderson} and R. E. {Howard} and W. {Hubbard} and L. D. {Jackel}}, journal={Neural Computation}, title={Backpropagation Applied to Handwritten Zip Code Recognition}, year={1989}, volume={1}, number={4}, pages={541-551}, doi={10.1162/neco.1989.1.4.541}} } ```