You trust one key (S/MIME or OpenPGP), but not the other? For this case, we have mutually signed each key with the other one. The directory `Signatures` contains the following two files:
* The S/MIME key signed with the OpenPGP key: [`Signatures/fs-coli@cl.uni-heidelberg.de.smime.pub.pem.sig`](Signatures/fs-coli@cl.uni-heidelberg.de.smime.pub.pem.sig)
* The OpenPGP key signed with the S/MIME key: [`Signatures/fs-coli@cl.uni-heidelberg.de.pgp.pub.asc.sig`](Signatures/fs-coli@cl.uni-heidelberg.de.pgp.pub.asc.sig)
By verifying the signature made with the key you already trust, you can verify that you can also trust the other key.