Update README.md

Author: chreman

README.md

@@ -74,7 +74,7 @@ More information can be found in the following papers:
 
 Kraker, P., Schramm, M., Kittel, C., Chamberlain, S., & Arrow, T. (2018). [VIPER: The Visual Project Explorer](https://zenodo.org/record/1248119). Zenodo. doi:10.5281/zenodo.2587129
 
-Kraker, P., Kittel, C., & Enkhbayar, A. (2016). [Open Knowledge Maps: Creating a Visual Interface to the World’s Scientific Knowledge Based on Natural Language Processing](http://0277.ch/ojs/index.php/cdrs_0277/article/view/157/355). 027.7 Journal for Library Culture, 4(2), 98–103. doi:10.12685/027.7-4-2-157
+Kraker, P., Kittel, C., & Enkhbayar, A. (2016). [Open Knowledge Maps: Creating a Visual Interface to the World’s Scientific Knowledge Based on Natural Language Processing](https://doi.org/10.12685/027.7-4-2-157). 027.7 Journal for Library Culture, 4(2), 98–103. doi:10.12685/027.7-4-2-157
 
 Kraker, P., Schlögl, C. , Jack, K. & Lindstaedt, S. (2015). [Visualization of Co-Readership Patterns from an Online Reference Management System](http://arxiv.org/abs/1409.0348). Journal of Informetrics, 9(1), 169–182. doi:10.1016/j.joi.2014.12.003