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"Statement of Information". businesssearch.sos.ca.gov. California Secretary of State. 28 August 2018. Archived from the original(PDF) on 24 January 2021. Retrieved 13 February 2019.
"Signal Messenger, LLC". OpenCorporates. Delaware Department of State: Division of Corporations. 15 July 2018. Archived from the original on 14 February 2019. Retrieved 13 February 2019.
"Statement of Information". businesssearch.sos.ca.gov. California Secretary of State. 3 October 2018. Archived from the original(PDF) on 14 February 2019. Retrieved 13 February 2019.