Create spectroscopy-letters

I've started working from the applied spectroscopy style as mentioned in the summary. 
There are still a few issues, but at least it seems to be compliant to 100% with journal references
Issue: a comma after the date still appears in the book references and I didn't know how to remove it. Probably it works with conditionals...)
These are the numbers from the other journals. I look such things normally in the <a href="http://ezb.uni-regensburg.de/detail.phtml?bibid=AAAAA&colors=7&lang=en&jour_id=9974">EZB</a> up:
```
P-ISSN(s): 	0038-7010
E-ISSN(s): 	1532-2289
```