10 Warning Signs You've Received a Fake Invoice Email https://www.armorblox.com/blog/fake-invoice-email-warning-signs/
Consumer Alert Phishers send fake invoices By Ari Lazarus February 23, 2018
https://consumer.ftc.gov/consumer-alerts/2018/02/phishers-send-fake-invoices
Overview of phishing techniques: Fake invoice/bills May 27, 2020 by Dan Virgillito https://resources.infosecinstitute.com/topic/overview-of-phishing-techniques-fake-invoice-bills/
1. 参考になる
7 Ways to Prevent Invoice and Email Fraud: A Comprehensive Guide Ben Frank Oct 25, 2021 14 min read
https://www.onpaysolutions.com/payment-blog/7-ways-to-prevent-invoice-and-email-fraud