medieval Bulgarian royal charters
...that the eight surviving medieval Bulgarian royal charters are among the few available secular documents from the time of the Second Bulgarian Empire?
...that the eight surviving <b id="mwAl0"><a href="./Medieval_Bulgarian_royal_charters" id="mwAl4" rel="mw:WikiLink" title="Medieval Bulgarian royal charters">medieval Bulgarian royal charters</a></b> are among the few available secular documents from the time of the <a href="./Second_Bulgarian_Empire" id="mwAl8" rel="mw:WikiLink" title="Second Bulgarian Empire">Second Bulgarian Empire</a>?