diff --git a/libraries/core/src/main/java/io/element/android/x/core/data/pmap.kt b/libraries/core/src/main/java/io/element/android/x/core/data/pmap.kt
index 8ec3a7fffe..36790dd426 100644
--- a/libraries/core/src/main/java/io/element/android/x/core/data/pmap.kt
+++ b/libraries/core/src/main/java/io/element/android/x/core/data/pmap.kt
@@ -4,6 +4,7 @@ import kotlinx.coroutines.async
 import kotlinx.coroutines.awaitAll
 import kotlinx.coroutines.coroutineScope
 
+// https://jivimberg.io/blog/2018/05/04/parallel-map-in-kotlin/
 suspend fun <A, B> Iterable<A>.parallelMap(f: suspend (A) -> B): List<B> = coroutineScope {
     map { async { f(it) } }.awaitAll()
 }
\ No newline at end of file