diff --git a/src/main.py b/src/main.py
index 8846b38..5f310a1 100644
--- a/src/main.py
+++ b/src/main.py
@@ -4,6 +4,55 @@ from APIHandler import APIHandler
 from classes import *
 
 
+def call_entrypoint_from_elabid(elabid):
+    try: 
+        sample_data = APIHandler(apikey).get_entry_from_elabid(elabid, entryType="items")
+        if not sample_data.get("category_title") == "Sample":
+            raise ValueError("The resource you selected is not a sample, therefore it can't be used as an entrypoint.")
+        sample_object = Entrypoint(sample_data)
+    except ConnectionError as e:
+        raise ConnectionError(e)
+    return sample_object # Entrypoint-class object
+
+def call_material_from_elabid(elabid):
+    try: 
+        material_data = APIHandler(apikey).get_entry_from_elabid(elabid, entryType="items")
+        # TO-DO: correct this typo on elabftw: Subtrate → Substrate.
+        if not sample_data.get("category_title") in ["PLD Target", "Substrate batch", "Subtrate batch"]:
+            raise ValueError(f"The referenced resource (elabid = {elabid}) is not a material.")
+        material_object = Material(material_data)
+    except ConnectionError as e:
+        raise ConnectionError(e)
+    return material_object # Material-class object
+
+def call_layers_from_list(elabid_list):
+    list_of_layers = []
+    for elabid in elabid_list:
+        try:
+            layer_data = APIHandler(apikey).get_entry_from_elabid(elabid, entryType="experiments")
+            if not layer_data.get("category_title") == "PLD Deposition":
+                continue
+            layer_object = Layer(layer_data)
+            list_of_layers.append(layer_object)        
+        except ConnectionError as e:
+            nums = [ layer.layer_number for layer in list_of_layers ]
+            nums.sort()
+            print(f"LISTA DEI LAYER PROCESSATI FINORA (in ordine sparso):\n" + str(nums))
+            raise ConnectionError(f"An error occurred while fetching the experiment with elabid = {elabid}:\n" +
+                str(e) + f"\nPlease solve the problem before retrying." + "\n\n" +
+                f"Last resource attempted to call: {ELABFTW_API_URL}/experiments/{elabid}"
+            )
+    return list_of_layers # list of Layer-class objects
+
+def from_entrypoint_to_material(sample_object):
+    material_elabid = sample_object.batch_elabid
+    material_object = call_material_from_elabid(material_elabid)
+    return sample_object, material_object
+
+sample_object = call_entrypoint_from_elabid(elabid)
+from_entrypoint_to_material(sample_object)
+    
+
 if __name__=="__main__":
     print(f"=======================\n===== DEBUG MODE! =====\n=======================\n")
     ELABFTW_API_URL = "https://elabftw.fisica.unina.it/api/v2"
@@ -19,14 +68,14 @@ if __name__=="__main__":
                 eT = eT[0]
             except Exception:
                 print("Usage: i|item|items|i[ELABID] for items, e|experiment|experiments|e[ELABID] for experiments.")
-                pass
+                continue
         match eT:
             case "items" | "i" | "item":
                 entryType = "items"
             case "experiments" | "e" | "exp" | "experiment":
                 entryType = "experiments"
             case _:
-                pass
+                continue
     # This will probably be reworked in production
     try:
         elabid = elabid