diff --git a/class-Queried.php b/class-Queried.php
index 0a83511..58469c7 100644
--- a/class-Queried.php
+++ b/class-Queried.php
@@ -1,185 +1,185 @@
 <?php
 # Copyright (C) 2017, 2018, 2019 Valerio Bozzolan
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
 # the Free Software Foundation, either version 3 of the License, or
 # (at your option) any later version.
 #
 # This program is distributed in the hope that it will be useful,
 # but WITHOUT ANY WARRANTY; without even the implied warranty of
 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 # GNU General Public License for more details.
 #
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 /**
  * This class handles a database table result
  *
  * Very often this database table has an ID and an UID.
  */
 class Queried {
 
 	/**
 	 * Maximum UID length
 	 */
 	const MAXLEN_UID = 256;
 
 	/**
 	 * Empty constructor
 	 */
 	public function __construct() {}
 
 	/**
 	 * Obtain a property that can be null (but can't be undefined).
 	 *
 	 * @param string $property
 	 * @return mixed
 	 */
 	public function get( $property ) {
 		if( property_exists( $this, $property ) ) {
 			return $this->$property;
 		}
 		throw new SucklessException( sprintf(
 			'cannot obtain %s->%s',
 			get_class( $this ),
 			$property
 		) );
 	}
 
 	/**
 	 * Check if a property is not NULL
 	 *
 	 * @param string $property
 	 * @return bool
 	 */
 	public function has( $property ) {
 		return null !== $this->get( $property );
 	}
 
 	/**
 	 * Obtain a property that can't be null (and can't be undefined).
 	 *
 	 * @param string $property
 	 * @return mixed
 	 */
 	public function nonnull($property) {
 		if( isset( $this->$property ) ) {
 			return $this->$property;
 		}
 		throw new SucklessException( sprintf(
 			'cannot obtain %s->%s',
 			get_class( $this ),
 			$property
 		) );
 	}
 
 	function integers() {
 		foreach( func_get_args() as $p) {
 			isset( $this->$p ) and
 				$this->$p = (int) $this->$p;
 		}
 		return $this;
 	}
 
 	function booleans() {
 		foreach( func_get_args() as $p) {
 			isset( $this->$p ) and
 				$this->$p = (bool) (int) $this->$p;
 		}
 		return $this;
 	}
 
 	function dates() {
 		foreach( func_get_args() as $p) {
 			isset( $this->$p ) and
 				$this->$p = DateTime::createFromFormat('Y-m-d', $this->$p);
 		}
 	}
 
 	function datetimes() {
 		foreach( func_get_args() as $p) {
 			isset( $this->$p ) and
 				$this->$p = DateTime::createFromFormat('Y-m-d H:i:s', $this->$p);
 		}
 		return $this;
 	}
 
 	function floats() {
 		foreach( func_get_args() as $p) {
 			isset( $this->$p ) and
 				$this->$p = (float) $this->$p;
 		}
 	}
 
 	/**
 	 * Query factory
 	 *
 	 * The class constant 'T' is expected as table name
 	 *
 	 * @return Query
 	 */
 	public static function factory() {
 		return Query::factory( static::class )
 			->from( static::T );
 	}
 
 	/**
 	 * Factory from an ID column
 	 *
 	 * The class constant 'ID' is expected
 	 *
 	 * @param $ID int
 	 * @return Queried
 	 */
 	public static function factoryFromID( $ID ) {
 		$field = defined( static::class . '::ID' ) ? static::ID : static::T . '_ID';
 		$field = static::T . DOT . $field;
-		return self::factory()
+		return static::factory()
 			->whereInt( $field, $ID );
 	}
 
 	/**
 	 * Factory from an UID column
 	 *
 	 * The class constant 'UID' is expected
 	 *
 	 * @param $uid string
 	 * @return Queried
 	 */
 	public static function factoryFromUID( $uid ) {
 		$field = defined( static::class . '::UID' ) ? static::UID : static::T . '_uid';
 		$uid = static::sanitizeUID( $uid );
-		return self::factory()
+		return static::factory()
 			->whereStr( $field, $uid );
 	}
 
 	/**
 	 * Sanitize the UID
 	 *
 	 * @return string
 	 * @use luser_input()
 	 */
 	public static function sanitizeUID( $uid ) {
 		return luser_input( $uid, static::MAXLEN_UID );
 	}
 
 	/**
 	 * Alias of self::factoryFromID()
 	 *
 	 * @deprecated
 	 */
 	public static function factoryByID( $ID ) {
 		return self::factoryFromID( $ID );
 	}
 
 	/**
 	 * Alias of self::factoryFromUID()
 	 *
 	 * @deprecated
 	 */
 	public static function factoryByUID( $uid ) {
 		return self::factoryFromUID( $uid );
 	}
 }