public static function images(array $aEmail, $iSize = null, $sDefaultImage = null, $sRating = null, $sExtension = null, $bForceDefault = false)
    {
        $aImages = [];

        foreach ($aEmail as $sEmail) {
            $gravatarImage = (new Image())
                ->setEmail($sEmail)
                ->setSize($iSize)
                ->setDefaultImage($sDefaultImage, $bForceDefault)
                ->setMaxRating($sRating)
                ->setExtension($sExtension);

            $aImages[$sEmail] = $gravatarImage;
        }

        return $aImages;
    }