diff --git a/src/algorithms/gcd/matrix.rs b/src/algorithms/gcd/matrix.rs
index 832e3973..b2138f5a 100644
--- a/src/algorithms/gcd/matrix.rs
+++ b/src/algorithms/gcd/matrix.rs
@@ -120,7 +120,7 @@ impl Matrix {
     ///
     /// # Panics
     ///
-    /// Panics if `r1 < r0`.
+    /// Panics if `r0 < r1`.
     // OPT: Would this be faster using extended binary gcd?
     // See <https://en.algorithmica.org/hpc/algorithms/gcd>
     #[inline]