# Contributions are welcome

I won't say no to any physical, chemical or mathematical constant as
long as

1. It's not there already. Please check
   out [terms](https://docs.perl6.org/language/terms#term_e) for those
   already in the core, like `e`.
   
2. You can find a reference for it, preferably Wikipedia, but anything
   else is OK. That means: if you are Bob and want to add Bob's
   constant, it's probably not a good idea. Please add the reference
   as a comment behind.
   
3. You write a test for it too. 

4. If possible, add an example where it could be used. 

5. If it's got some one-letter equivalent, please alias it to that
   letter too. For instance, `plancks-reduced-h` is aliased to `ℏ`.
   
If your constant is used, like `c`, as a measure, you can also add a
postfix function so that it can also be used that way.