docs: def add_ref(self, wordlist):
  		"""
  		Adds a reference.
  		"""
  		refname = wordlist[0][:-1]
  
  		if(refname in self.refs):
  			raise ReferenceError("[line {}]:{} already defined here (word) {} (line) {}".format(self.line_count, 
  						refname, self.refs[refname][0], self.refs[refname][1]))
  		self.refs[refname] = (self.word_count, self.line_count)