Norwegian Princess Martha Louise, who has set up her own alternative medicine business, has published her second book about angels, advising readers on how to talk to them.

There are an infinite number of angels all around us who want to help us in all circumstances and at all times,” the 40-year-old princess and fellow author Elisabeth Nordeng wrote in their introduction to the book The Secrets of Angels.

“They are there for us. They are real. They exist,” they added.

The book is a sequel to Discover Your Guardian Angel which the two women published in 2009.

“In The Secrets of Angels we reveal some of their secrets to make it easier for you to contact them. Angels want to be in touch with you, but it’s important to know how they operate and how they get in touch,” the two women authors said.

The princess, who is fourth in line of succession to the Norwegian crown, has renounced her title of Princess Royal along with most of her official duties in order to lead her own private life. She is often mocked in her own country for having founded a “school of angels”.