Mexico's third-richest billionaire, Ricardo Salinas Pliego, gave some advice Saturday about investing in bitcoin.

Salinas is the founder and chairman of Grupo Salinas, a group of companies with interests in telecommunications, media, financial services, and retail stores. According to Forbes' list of billionaires, his net worth is currently more than $13 billion.

The billionaire tweeted Saturday urging his Twitter followers to buy bitcoin and keep buying while the price of BTC is still low. His tweet reads:

You have to buy bitcoin (keep buying when the price is low), then just hold your BTC, forget about selling … Trust me you're going to thank me later.

Bitcoin has fallen more than 40% since its all-time high in November last year. A number of people and corporations have bought the dip, including the Nasdaq-listed Microstrategy, U.S. Senator Ted Cruz, and the government of El Salvador.

This is not the first time Salinas has strongly recommended buying bitcoin. He explained in June last year: "Bitcoin is an asset that has extraordinary properties … All the advantages that bitcoin has, for me, make it gold for the modern world."