diff --git a/htdocs/core/modules/supplier_invoice/mod_facture_fournisseur_cactus.php b/htdocs/core/modules/supplier_invoice/mod_facture_fournisseur_cactus.php
index f753d8b2fce..7e1febf3189 100644
--- a/htdocs/core/modules/supplier_invoice/mod_facture_fournisseur_cactus.php
+++ b/htdocs/core/modules/supplier_invoice/mod_facture_fournisseur_cactus.php
@@ -20,11 +20,11 @@
 
 /**
  *    	\file       htdocs/core/modules/supplier_order/mod_facture_fournisseur_cactus.php
- *		\ingroup    commande
+ *		\ingroup    supplier invoice
  *		\brief      File containing the Cactus Class of numbering models of suppliers invoices references
  */
 
-require_once DOL_DOCUMENT_ROOT .'/core/modules/supplier_order/modules_facturefournisseur.php';
+require_once DOL_DOCUMENT_ROOT .'/core/modules/supplier_invoice/modules_facturefournisseur.php';
 
 
 /**
@@ -123,7 +123,7 @@ class mod_facture_fournisseur_cactus extends ModeleNumRefSuppliersInvoices
 
 		//$date=time();
         $date=$object->datec;   // Not always defined
-        if (empty($date)) $date=$object->date;  // Creation date is order date for suppliers orders
+        if (empty($date)) $date=$object->date;  // Creation date is invoice date for suppliers invoices
         $yymm = strftime("%y%m",$date);
         $num = sprintf("%04s",$max+1);
 
diff --git a/htdocs/core/modules/supplier_invoice/mod_facture_fournisseur_tulip.php b/htdocs/core/modules/supplier_invoice/mod_facture_fournisseur_tulip.php
index 72cf50adc60..d0ee9e23738 100644
--- a/htdocs/core/modules/supplier_invoice/mod_facture_fournisseur_tulip.php
+++ b/htdocs/core/modules/supplier_invoice/mod_facture_fournisseur_tulip.php
@@ -123,7 +123,7 @@ class mod_facture_fournisseur_tulip extends ModeleNumRefSuppliersInvoices
 			return 0;
 		}
 
-		$numFinal=get_next_value($db,$mask,'facture_fournisseur','ref','',$objsoc->code_fournisseur,$object->date_commande);
+		$numFinal=get_next_value($db,$mask,'facture_fournisseur','ref','',$objsoc->code_fournisseur,$object->datec);
 
 		return  $numFinal;
 	}
diff --git a/htdocs/core/modules/supplier_invoice/modules_facturefournisseur.php b/htdocs/core/modules/supplier_invoice/modules_facturefournisseur.php
index 7a80cc93bfe..6be7100c14e 100755
--- a/htdocs/core/modules/supplier_invoice/modules_facturefournisseur.php
+++ b/htdocs/core/modules/supplier_invoice/modules_facturefournisseur.php
@@ -22,6 +22,7 @@
  *		\file       htdocs/core/modules/supplier_invoice/modules_facturefournisseur.php
  *      \ingroup    facture fournisseur
  *      \brief      File that contains parent class for supplier invoices models
+ *					and parent class for supplier invoices numbering models
  */
 require_once DOL_DOCUMENT_ROOT.'/core/class/commondocgenerator.class.php';
 require_once DOL_DOCUMENT_ROOT.'/compta/bank/class/account.class.php';	// requis car utilise par les classes qui heritent
@@ -36,7 +37,7 @@ abstract class ModelePDFSuppliersInvoices extends CommonDocGenerator
 
 
 	/**
-	 *  Return list of active generation modules
+	 *  Return list of active generation models
 	 *
      *  @param	DoliDB	$db     			Database handler
      *  @param  string	$maxfilenamelength  Max length of value to show
@@ -131,7 +132,7 @@ abstract class ModeleNumRefSuppliersInvoices
 }
 
 /**
- *	Create a document onto disk according to template module.
+ *	Create a document onto disk according to template model.
  *
  *	@param	    DoliDB		$db  			Database handler
  *	@param	    Object		$object			Object supplier invoice
@@ -158,7 +159,7 @@ function supplier_invoice_pdf_create($db, $object, $modele, $outputlangs, $hided
 
     $srctemplatepath='';
 
-	// Positionne le modele sur le nom du modele a utiliser
+	// Set the model on the model name to use
 	if (! dol_strlen($modele))
 	{
 		if (! empty($conf->global->INVOICE_SUPPLIER_ADDON_PDF))
@@ -189,7 +190,7 @@ function supplier_invoice_pdf_create($db, $object, $modele, $outputlangs, $hided
 		{
 			$file = $prefix."_".$modele.".modules.php";
 
-			// On verifie l'emplacement du modele
+			// We checked the location of the model
 			$file=dol_buildpath($reldir."core/modules/supplier_invoice/pdf/".$file,0);
 			if (file_exists($file))
 			{
@@ -201,7 +202,7 @@ function supplier_invoice_pdf_create($db, $object, $modele, $outputlangs, $hided
 		if ($filefound) break;
 	}
 
-	// Charge le modele
+	// Load the model
 	if ($filefound)
 	{
 		require_once $file;
@@ -219,12 +220,12 @@ function supplier_invoice_pdf_create($db, $object, $modele, $outputlangs, $hided
         	require_once DOL_DOCUMENT_ROOT.'/core/lib/files.lib.php';
 			dol_delete_preview($object);
 
-			// Appel des triggers
+			// Calls triggers
 			include_once DOL_DOCUMENT_ROOT . '/core/class/interfaces.class.php';
 			$interface=new Interfaces($db);
 			$result=$interface->run_triggers('BILL_INVOICE_BUILDDOC',$object,$user,$langs,$conf);
 			if ($result < 0) { $error++; $this->errors=$interface->errors; }
-			// Fin appel triggers
+			// End calls triggers
 
 			return 1;
 		}
@@ -238,7 +239,14 @@ function supplier_invoice_pdf_create($db, $object, $modele, $outputlangs, $hided
 	}
 	else
 	{
-		print $langs->trans("Error")." ".$langs->trans("ErrorFileDoesNotExists",$file);
+		if (! $conf->global->INVOICE_SUPPLIER_ADDON_PDF)
+		{
+			print $langs->trans("Error")." ".$langs->trans("Error_INVOICE_SUPPLIER_ADDON_PDF_NotDefined");
+		}
+		else
+		{
+			print $langs->trans("Error")." ".$langs->trans("ErrorFileDoesNotExists",$file);
+		}
 		return 0;
 	}
 }