diff --git a/README.md b/README.md
index 65a9a86..4118056 100644
--- a/README.md
+++ b/README.md
@@ -17,6 +17,8 @@ This project is developed and maintained by the [Resources team][team].
   - [Community](#community)
     - [Community Chat Rooms](#community-chat-rooms)
   - [Books, blogs, and training materials](#books-blogs-and-training-materials)
+    - [Free and public materials](#free-and-public-materials)
+    - [Paid and commercially available materials](#paid-and-commercially-available-materials)
   - [Tools](#tools)
   - [Real-time](#real-time)
     - [Real-time Operating System (RTOS)](#real-time-operating-system-rtos)
@@ -805,6 +807,7 @@ Otherwise, please add it to the [WIP section](#wip) below.
 1. [FUSB302B] - I2C - Programmable USB Type‐C Controller with USB Power Delivery - [github][69]
 1. [HC-12] - SERIAL - Wireless serial transceiver module - [Intro blog post][56] - [github][53] - [![crates.io](https://img.shields.io/crates/v/hc12-at.svg)](https://crates.io/crates/hc12-at)
 1. [HTS221] - I2C - Humidity and temperature sensor - [Intro blog post][7] - [![crates.io](https://img.shields.io/crates/v/hts221.svg)](https://crates.io/crates/hts221)
+1. [IS31FL3728] - I2C -  LED dot matrix display mode (8×8, 5x11, 6x10,7x9) - [github](https://github.com/leonidv/is31fl3728-rs) -[![crates.io](https://img.shields.io/crates/v/is31fl3728-rs)](https://crates.io/crates/is31fl3728-rs)
 1. [IIS2MDC] - I2C - ST's High accuracy, ultra-low-power, 3-axis digital output magnetometer - [![crates.io](https://img.shields.io/crates/v/iis2mdc.svg)](https://crates.io/crates/iis2mdc)
 1. [ISM330DHCX] - I2C - ST's IMU with 3D accelerometer, 3D gyroscope, ML core and more - [![crates.io](https://img.shields.io/crates/v/ism330dhcx.svg)](https://crates.io/crates/ism330dhcx)
 1. [keypad] - GPIO - Keypad matrix circuits - [Intro post][14] - [![crates.io](https://img.shields.io/crates/v/keypad.svg)](https://crates.io/crates/keypad)
@@ -963,6 +966,7 @@ Otherwise, please add it to the [WIP section](#wip) below.
 [FH101RF]: https://crates.io/crates/fh101rf
 [FUSB302B]: https://github.com/fmckeogh/usb-pd-rs
 [HTS221]: https://crates.io/crates/hts221
+[IS31FL3728]: https://crates.io/crates/is31fl3728-rs
 [IIS2MDC]: https://crates.io/crates/iis2mdc
 [ISM330DHCX]: https://crates.io/crates/ism330dhcx
 [keypad]: https://crates.io/crates/keypad