diff --git a/README.md b/README.md
index c324857..baaf459 100644
--- a/README.md
+++ b/README.md
@@ -99,4 +99,15 @@ modules/
                 sqrt_omp.h
                 mul_omp.h
             sqrt.h 
-```
\ No newline at end of file
+```
+
+
+```text
+Matrix C = mul(A, B);          // allocate/return result
+Status s = mul_into(A, B, C);  // write into existing matrix
+Status s = add_inplace(A, B);  // modify A itself
+or overloading?
+```
+
+
+