diff --git a/src/rsprocess/bisimilarity.rs b/src/rsprocess/bisimilarity.rs
index 7443e08..372aa14 100644
--- a/src/rsprocess/bisimilarity.rs
+++ b/src/rsprocess/bisimilarity.rs
@@ -1,21 +1,11 @@
 use std::collections::{BTreeSet, HashMap};
 
-use petgraph::visit::{EdgeIndexable, EdgeRef, IntoEdgeReferences, IntoEdges, IntoNodeReferences, NodeIndexable};
-
-
-
-
-
-
-#[allow(dead_code)]
-fn print_type_of<T>(_: &T) {
-    println!("type: {}", std::any::type_name::<T>());
-}
-
-
-
-
-
+use petgraph::visit::{ EdgeIndexable,
+		       EdgeRef,
+		       IntoEdgeReferences,
+		       IntoEdges,
+		       IntoNodeReferences,
+		       NodeIndexable };
 
 struct GraphPartition<'a, G>
 where
@@ -30,6 +20,25 @@ where
     blocks: BTreeSet<u32>
 }
 
+
+fn equal_vectors<T>(a: &Vec<T>, b: &Vec<T>) -> bool
+where
+    T: PartialEq
+{
+    for el in a {
+	if !b.contains(el) {
+	    return false;
+	}
+    }
+
+    for el in b {
+	if !a.contains(el) {
+	    return false;
+	}
+    }
+    true
+}
+
 impl<'a, G> GraphPartition<'a, G>
 where
     G: EdgeIndexable + NodeIndexable + IntoEdgeReferences + IntoNodeReferences
@@ -74,12 +83,13 @@ where
 	&self,
 	label: &G::EdgeRef,
 	s: &(usize, G::NodeId)
-    ) -> Vec<(usize, G::NodeId)>
+    ) -> Vec<u32>
     where <G as IntoEdgeReferences>::EdgeRef: PartialEq
     {
 	let mut val = vec![];
 	for el in self.graphs[s.0].edges(s.1).filter(|x| x == label) {
-	    val.push((s.0, el.target()));
+	    let tmp = (s.0, el.target());
+	    val.push(*self.node_to_block.get(&tmp).unwrap());
 	}
 	val
     }
@@ -99,15 +109,13 @@ where
 
 	let reachable_blocks_s = self.reachable_blocks(label, s);
 
-	'outer: for t in nodes {
+	for t in nodes {
 	    let reachable_blocks_t = self.reachable_blocks(label, t);
-	    for rbt in reachable_blocks_t {
-		if !reachable_blocks_s.contains(&rbt) {
-		    b2.push(*t);
-		    continue 'outer;
-		}
+	    if equal_vectors(&reachable_blocks_s, &reachable_blocks_t) {
+		b1.push(t);
+	    } else {
+		b2.push(*t);
 	    }
-	    b1.push(t);
 	}
 
 	if b2.is_empty() {
diff --git a/src/rsprocess/structure.rs b/src/rsprocess/structure.rs
index bb47399..d49b18e 100644
--- a/src/rsprocess/structure.rs
+++ b/src/rsprocess/structure.rs
@@ -11,8 +11,7 @@ use serde::{Deserialize, Serialize};
 // -----------------------------------------------------------------------------
 
 /// Basic set of entities.
-#[derive(Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash, Serialize,
-	 Deserialize)]
+#[derive(Clone, Debug, PartialOrd, Eq, Ord, Hash, Serialize, Deserialize)]
 pub struct RSset {
     pub identifiers: BTreeSet<IdType>,
 }
@@ -118,6 +117,12 @@ impl Default for RSset {
     }
 }
 
+impl PartialEq for RSset {
+    fn eq(&self, other: &Self) -> bool {
+	self.identifiers.eq(&other.identifiers)
+    }
+}
+
 impl IntoIterator for RSset {
     type Item = IdType;
     type IntoIter = std::collections::btree_set::IntoIter<Self::Item>;
@@ -491,7 +496,7 @@ impl Default for RSsystem {
 // -----------------------------------------------------------------------------
 // RSlabel
 // -----------------------------------------------------------------------------
-#[derive(Clone, Debug, Serialize, Deserialize, PartialEq, Eq, PartialOrd)]
+#[derive(Clone, Debug, Serialize, Deserialize, Eq, PartialOrd)]
 pub struct RSlabel {
     pub available_entities: RSset,
     pub context: RSset,
@@ -555,6 +560,19 @@ impl Default for RSlabel {
     }
 }
 
+impl PartialEq for RSlabel {
+    fn eq(&self, other: &Self) -> bool {
+	self.available_entities == other.available_entities &&
+	    self.context == other.context &&
+	    self.t == other.t &&
+	    self.reactants == other.reactants &&
+	    self.reactants_absent == other.reactants_absent &&
+	    self.inhibitors == other.inhibitors &&
+	    self.inhibitors_present == other.inhibitors_present &&
+	    self.products == other.products
+    }
+}
+
 // -----------------------------------------------------------------------------
 // RSassertOp
 // -----------------------------------------------------------------------------
diff --git a/testing/first.system b/testing/first.system
index f261659..1c7e3ae 100644
--- a/testing/first.system
+++ b/testing/first.system
@@ -4,4 +4,4 @@ Context: [({a,b}.{a}.{a,c}.x + {a,b}.{a}.{a}.nill)]
 Reactions: ([{a,b}, {c}, {b}])
 
 
-Bisimilarity ("testing/adversarial.system") > Print
\ No newline at end of file
+Bisimilarity ("testing/first.system") > Print