diff --git a/LICENSE.md b/LICENSE.md
index 96fab37..b3cf9ee 100644
--- a/LICENSE.md
+++ b/LICENSE.md
@@ -19,3 +19,6 @@ The ExponentialUtilities.jl package is licensed under the MIT "Expat" License:
 > LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 > OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 > SOFTWARE.
+
+The KIOPS implementation is derived from https://gitlab.com/stephane.gaudreault/jcp2021_highorder_sw/-/blob/master/kiops.py
+with licensing approved by the original author.