fix: validation for internal transfer entry
diff --git a/erpnext/accounts/doctype/sales_invoice/sales_invoice.js b/erpnext/accounts/doctype/sales_invoice/sales_invoice.js
index 56e412b..8cb2950 100644
--- a/erpnext/accounts/doctype/sales_invoice/sales_invoice.js
+++ b/erpnext/accounts/doctype/sales_invoice/sales_invoice.js
@@ -334,6 +334,7 @@
 	}
 
 	make_inter_company_invoice() {
+		let me = this;
 		frappe.model.open_mapped_doc({
 			method: "erpnext.accounts.doctype.sales_invoice.sales_invoice.make_inter_company_purchase_invoice",
 			frm: me.frm
diff --git a/erpnext/controllers/accounts_controller.py b/erpnext/controllers/accounts_controller.py
index c741622..642d51c 100644
--- a/erpnext/controllers/accounts_controller.py
+++ b/erpnext/controllers/accounts_controller.py
@@ -5,7 +5,7 @@
 import json
 
 import frappe
-from frappe import _, throw
+from frappe import _, bold, throw
 from frappe.model.workflow import get_workflow_name, is_transition_condition_satisfied
 from frappe.query_builder.functions import Abs, Sum
 from frappe.utils import (
@@ -405,6 +405,15 @@
 				msg += _("Please create purchase from internal sale or delivery document itself")
 				frappe.throw(msg, title=_("Internal Sales Reference Missing"))
 
+			label = "Delivery Note Item" if self.doctype == "Purchase Receipt" else "Sales Invoice Item"
+
+			field = frappe.scrub(label)
+
+			for row in self.get("items"):
+				if not row.get(field):
+					msg = f"At Row {row.idx}: The field {bold(label)} is mandatory for internal transfer"
+					frappe.throw(_(msg), title=_("Internal Transfer Reference Missing"))
+
 	def disable_pricing_rule_on_internal_transfer(self):
 		if not self.get("ignore_pricing_rule") and self.is_internal_transfer():
 			self.ignore_pricing_rule = 1
diff --git a/erpnext/stock/doctype/purchase_receipt/test_purchase_receipt.py b/erpnext/stock/doctype/purchase_receipt/test_purchase_receipt.py
index 8af279a..c34f9da 100644
--- a/erpnext/stock/doctype/purchase_receipt/test_purchase_receipt.py
+++ b/erpnext/stock/doctype/purchase_receipt/test_purchase_receipt.py
@@ -1693,6 +1693,64 @@
 		# Value of Stock Account should be equal to the sum of Stock Value Difference
 		self.assertEqual(stock_account_value, stock_diff)
 
+	def test_internal_pr_reference(self):
+		item = make_item(properties={"is_stock_item": 1, "valuation_rate": 100})
+		customer = "_Test Internal Customer 2"
+		company = "_Test Company with perpetual inventory"
+		from_warehouse = create_warehouse("_Test Internal From Warehouse New 1", company=company)
+		target_warehouse = create_warehouse("_Test Internal GIT Warehouse New 1", company=company)
+		to_warehouse = create_warehouse("_Test Internal To Warehouse New 1", company=company)
+
+		# Step 2: Create Stock Entry (Material Receipt)
+		from erpnext.stock.doctype.stock_entry.test_stock_entry import make_stock_entry
+
+		make_stock_entry(
+			purpose="Material Receipt",
+			item_code=item.name,
+			qty=15,
+			company=company,
+			to_warehouse=from_warehouse,
+		)
+
+		# Step 3: Create Delivery Note with Internal Customer
+		from erpnext.stock.doctype.delivery_note.test_delivery_note import create_delivery_note
+
+		dn = create_delivery_note(
+			item_code=item.name,
+			company=company,
+			customer=customer,
+			cost_center="Main - TCP1",
+			expense_account="Cost of Goods Sold - TCP1",
+			qty=10,
+			rate=100,
+			warehouse=from_warehouse,
+			target_warehouse=target_warehouse,
+		)
+
+		# Step 4: Create Internal Purchase Receipt
+		from erpnext.controllers.status_updater import OverAllowanceError
+		from erpnext.stock.doctype.delivery_note.delivery_note import make_inter_company_purchase_receipt
+
+		pr = make_inter_company_purchase_receipt(dn.name)
+		pr.inter_company_reference = ""
+		self.assertRaises(frappe.ValidationError, pr.save)
+
+		pr.inter_company_reference = dn.name
+		pr.items[0].qty = 10
+		pr.items[0].from_warehouse = target_warehouse
+		pr.items[0].warehouse = to_warehouse
+		pr.items[0].rejected_warehouse = from_warehouse
+		pr.save()
+
+		delivery_note_item = pr.items[0].delivery_note_item
+		pr.items[0].delivery_note_item = ""
+
+		self.assertRaises(frappe.ValidationError, pr.save)
+
+		pr.load_from_db()
+		pr.items[0].delivery_note_item = delivery_note_item
+		pr.save()
+
 
 def prepare_data_for_internal_transfer():
 	from erpnext.accounts.doctype.sales_invoice.test_sales_invoice import create_internal_supplier