Would this work?:
```
//! [1]: Pedro Celis. ["Robin Hood Hashing"](https://cs.uwaterloo.ca/research/tr/1986/CS-86-14.pdf)
//! [2]: (http://codecapsule.com/2013/11/11/robin-hood-hashing/)
//! [3]: (http://codecapsule.com/2013/11/17/robin-hood-hashing-backward-shift-deletion/)
```