Update readme

Author: adipandas

REFERENCES.md

@@ -1,7 +1,9 @@
 # References and Credits
 
-[Home](https://adipandas.github.io/multi-object-tracker/){: .btn .btn-green }
-[GitHub](https://github.com/adipandas/multi-object-tracker){: .btn .btn-blue}
+<p>
+<button name="button1" onclick="https://adipandas.github.io/multi-object-tracker/">Home</button>
+<button name="button2" onclick="https://github.com/adipandas/multi-object-tracker">GitHub</button>
+</p>
 
 This work is based on the following literature: