diff --git a/scripts/base/frameworks/sumstats/plugins/topk.zeek b/scripts/base/frameworks/sumstats/plugins/topk.zeek
index e7107cb4fb..683d141467 100644
--- a/scripts/base/frameworks/sumstats/plugins/topk.zeek
+++ b/scripts/base/frameworks/sumstats/plugins/topk.zeek
@@ -1,4 +1,9 @@
 ##! Keep the top-k (i.e., most frequently occurring) observations.
+##!
+##! This plugin uses a probabilistic algorithm to count the top-k elements.
+##! The algorithm (calles Space-Saving) is described in the paper Efficient
+##! Computation of Frequent and Top-k Elements in Data Streams", by
+##! Metwally et al. (2005).
 
 @load base/frameworks/sumstats
 
diff --git a/src/probabilistic/Topk.h b/src/probabilistic/Topk.h
index 10238bef98..2229d82206 100644
--- a/src/probabilistic/Topk.h
+++ b/src/probabilistic/Topk.h
@@ -7,8 +7,11 @@
 #include "zeek/OpaqueVal.h"
 #include "zeek/Val.h"
 
-// This class implements the top-k algorithm. Or - to be more precise - an
-// interpretation of it.
+// This class implements the Space-Saving algorithm for counting the Topk- elements
+// in a datastream as presented in the paper "Efficient Computation of Frequent and
+// Top-k Elements in Data Streams", by Metwally et al. (2005).
+//
+// Or - to be more precise - it implements an interpretation of it.
 
 namespace zeek::detail
 	{