public static function rangeBoundaries($pRange = 'A1:A1')
    {
        // Ensure $pRange is a valid range
        if (empty($pRange)) {
            $pRange = self::DEFAULT_RANGE;
        }

        // Uppercase coordinate
        $pRange = strtoupper($pRange);

        // Extract range
        if (strpos($pRange, ':') === false) {
            $rangeA = $rangeB = $pRange;
        } else {
            list($rangeA, $rangeB) = explode(':', $pRange);
        }

        // Calculate range outer borders
        $rangeStart = self::coordinateFromString($rangeA);
        $rangeEnd    = self::coordinateFromString($rangeB);

        // Translate column into index
        $rangeStart[0]    = self::columnIndexFromString($rangeStart[0]);
        $rangeEnd[0]    = self::columnIndexFromString($rangeEnd[0]);

        return array($rangeStart, $rangeEnd);
    }