diff --git a/dfilters b/dfilters
index 5a89fafac7..7a84d508f8 100644
--- a/dfilters
+++ b/dfilters
@@ -13,4 +13,4 @@
 "TCP or UDP port is 80 (HTTP)" tcp.port == 80 || udp.port == 80
 "HTTP" http
 "No ARP and no DNS" not arp and !(udp.port == 53)
-"Non-HTTP and non-SMTP to/from 192.0.2.1" ip.addr == 192.0.2.1 and not tcp.port in {80 25}
+"Non-HTTP and non-SMTP to/from 192.0.2.1" ip.addr == 192.0.2.1 and tcp.port not in {80, 25}
diff --git a/docbook/wsug_src/WSUG_chapter_work.adoc b/docbook/wsug_src/WSUG_chapter_work.adoc
index 50c63b8bc4..9dc613e1f4 100644
--- a/docbook/wsug_src/WSUG_chapter_work.adoc
+++ b/docbook/wsug_src/WSUG_chapter_work.adoc
@@ -681,7 +681,7 @@ You can combine filter expressions in Wireshark using the logical operators show
 |xor     |^^        | Logical XOR   | `tr.dst[0:3] == 0.6.29 xor tr.src[0:3] == 0.6.29`
 |not     |!         | Logical NOT   | `not llc`
 |[...]   |          | Subsequence   | See “Slice Operator” below.
-|in      |          | Set Membership| http.request.method in {"HEAD" "GET"}. See “Membership Operator” below.
+|in      |          | Set Membership| http.request.method in {"HEAD", "GET"}. See “Membership Operator” below.
 |===
 
 ==== Slice Operator
@@ -724,14 +724,15 @@ to form compound ranges as shown above.
 Wireshark allows you to test a field for membership in a set of values or
 fields. After the field name, use the `in` operator followed by the set items
 surrounded by braces {}. For example, to display packets with a TCP source or
-destination port of 80, 443, or 8080, you can use `tcp.port in {80 443 8080}`.
-The set of values can also contain ranges: `tcp.port in {443 4430..4434}`.
+destination port of 80, 443, or 8080, you can use `tcp.port in {80, 443, 8080}`.
+Set elements must be separated by commas.
+The set of values can also contain ranges: `tcp.port in {443,4430..4434}`.
 
 [NOTE]
 ====
 The display filter
 ----
-tcp.port in {80 443 8080}
+tcp.port in {80, 443, 8080}
 ----
 is equivalent to
 ----
@@ -739,7 +740,7 @@ tcp.port == 80 || tcp.port == 443 || tcp.port == 8080
 ----
 However, the display filter
 ----
-tcp.port in {443 4430..4434}
+tcp.port in {443, 4430..4434}
 ----
 is not equivalent to
 ----
@@ -756,8 +757,8 @@ membership operator tests a single field against the range condition.
 
 Sets are not just limited to numbers, other types can be used as well:
 ----
-http.request.method in {"HEAD" "GET"}
-ip.addr in {10.0.0.5 .. 10.0.0.9 192.168.1.1..192.168.1.9}
+http.request.method in {"HEAD", "GET"}
+ip.addr in {10.0.0.5 .. 10.0.0.9, 192.168.1.1..192.168.1.9}
 frame.time_delta in {10 .. 10.5}
 ----