AAAARRGGGHH apparently you just can't store references in a container like this...
Yes, you can, all you need to do is declare that the vector is suppose to store pointers, like this:
Take note of the asterisk. This will store an array of pointers for "Thing" into otherVector. The way you have it set up right now, otherVector is in fact storing an array of "Thing" objects themselves, rather than references to them.