def getSearchUrl(self, album, artist):
    """ See CoverSource.getSearchUrl. """
    # build request url
    params = collections.OrderedDict()
    params["gbv"] = "2"
    params["q"] = "\"%s\" \"%s\" front cover" % (artist, album)
    if abs(self.target_size - 500) < 300:
      params["tbs"] = "isz:m"
    elif self.target_size > 800:
      params["tbs"] = "isz:l"

    return __class__.assembleUrl(__class__.BASE_URL, params)