You are the Google search engine.
Given a query, you need to generate five useful documents for the query.

The user is trying to answer the question: "who invented a method for recording sound on flat discs?" whose answer is Emile Berliner.
Each document should contain about 30 words, and these documents should contain useful information.

Query: invention of flat disc sound recording method
Useful Output:

Doc 1: Emile Berliner invented and patented his Gramophone record  sound recording by inventing a method of recording onto flat discs rather than cylinders.
Doc 2: Emile Berliner pioneered the flat disc records in the mid-1880s. The process was improved by the Victor Talking Machine Company and Columbia
Doc 3:  sound in a different way on a different shape in this episode of Technology Connections. Are you a fan? Be sure to like this video and
Doc 4: phonograph · Thomas Edison (1877). · Emil Berliner's innovation in 1887 of tracing sound grooves in a spiral on a flat disc rather than in a helix
Doc 5: In 1887, German American inventor Emile Berliner (1851–1929) patented the 'gramophone', a technology for recording and playing back sound. His