Multi-line text/comment/description in REST interface

I have been trying to use the REST interface through PHP cURL and the
content=>value uses new lines (\n) to delimit fields so how do you embed
new lines into the Text: field?

T-Mobile (UK) Limited
Company Registered Number: 02382161
Registered Office Address: Hatfield Business Park, Hatfield, Hertfordshire, AL10 9BW
Registered in England and Wales


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