diff --git a/How-to-use-lexicon-DNS-API.md b/How-to-use-lexicon-DNS-API.md
index e0b597c..d83de1a 100644
--- a/How-to-use-lexicon-DNS-API.md
+++ b/How-to-use-lexicon-DNS-API.md
@@ -21,6 +21,8 @@ You can check its project page: https://github.com/AnalogJ/lexicon
 
 You must install `python` and `lexicon` before using it.
 
+For more examples, please check lexicon page: https://github.com/AnalogJ/lexicon
+
 ## Examples:
 ### 1. Using lexicon cloudflare api:
 ```
@@ -51,7 +53,37 @@ export LEXICON_TRANSIP_API_KEY="/path/to/file.key"
 acme.sh --issue  -d test.acme.sh  --dns  dns_lexicon
 ```
 
-For more examples, please check lexicon page: https://github.com/AnalogJ/lexicon
+### 4. Using Technitium DNS via Lexicon `ddns` API:
 
+In this example, we request a DNS-01-challenged ACME certificate using a custom (internal) ACME server via the Lexicon API via [Technitium DNS](https://technitium.com/dns/). Note that we use `--dnssleep 0` to skip the public DNS check (since this is for an internal DNS setup).
 
+There are some prerequisites to setup TSIG within Technitium. In Technitium's Web UI:
 
+* Create a TSIG Key via Settings>TSIG. Set `<KeyName>`, `<Algorithm>`, and optionally `<SharedSecret>` (if you don't set Shared Secret, Technitium will create one for you when you click "Save"). For example:
+   * KeyName: `lexicon`
+   * SharedSecret: `12345abcde` (NOTE: this is just an example!)
+   * Algorithm: `HMAC-SHA256`
+* Enable Zone Transfer and Dynamic Updates at Zones > `example.com` > Options > Zone Options.
+   * [Zone Transfer tab] Zone Transfer: `Allow`
+   * [Zone Transfer tab] Zone Transfer TSIG Key Names: `<KeyName>` from above - optionally you can select your KeyName from "Quick Add" menu
+   * [Dynamic Updates tab] Dynamic Updates: `Allow` (use "Specified IP Addresses" if possible)
+   * [Dynamic Updates tab] Add a security policy with the following options:
+      * TSIG Key Name: `<KeyName>`
+      * Domain Name: `*.example.com`
+      * Allowed Record Types: `TXT`
+
+In your `acme.sh` CLI session:
+
+```
+export PROVIDER=ddns
+# Format: export LEXICON_DDNS_DDNS_SERVER=<DNS Server IP>
+export LEXICON_DDNS_DDNS_SERVER=10.1.0.5
+# Format: export LEXICON_DDNS_TOKEN=<Algorithm>:<KeyName>:<SharedSecret>
+export LEXICON_DDNS_TOKEN=hmac-sha256:lexicon:12345abcde
+
+acme.sh --issue \
+    -d test.example.com \
+    --dns dns_lexicon \
+    --server https://hcv.ff.lan/v1/pki_int/acme/directory \
+    --dnssleep 0
+```
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