import re


def find_cite_keys(markdown):
    """
    Finds the cite keys in the markdown text
    This function can handle multiple keys in a single reference

    Args:
        markdown (str): the markdown text to be extract citation
                        keys from
    """

    cite_regex = re.compile(r"(\[(?:@\w+;{0,1}\s*)+\])")
    cite_keys = cite_regex.findall(markdown)
    return list(cite_keys)