def encode_values(values):
    """Encode a given list of cell values into utf-8 format.

    Parameters
    ----------
    values: list(string)

    Returns
    -------
    list(string)
    """
    result = list()
    for val in values:
        if isinstance(val, str):
            try:
                result.append(val)
            except UnicodeDecodeError as ex:
                try:
                    result.append(val.decode('cp1252').encode('utf-8'))
                except UnicodeDecodeError as ex:
                    result.append(val.decode('latin1').encode('utf-8'))
        else:
            result.append(val)
    return result
