The race to provide customers with instant access to everything just got a lot more intense.

In a bid to take on rival Amazon, Google and Barnes & Noble are partnering up to provide same-day book delivery. Beginning today, customers in certain parts of New York City, Los Angeles and the San Francisco area can receive the books they order from local Barnes & Noble stores in a matter of hours.

The books will be delivered through Google's year-old shopping service, Google Shopping Express, which lets customers order items for same-day delivery from retailers such as Whole Foods and Guitar Center.

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"We're excited that people in the San Francisco Bay Area, West LA and Manhattan will be able to use Google Shopping Express to get same day deliveries from Barnes & Noble, joining our existing retail partners like Target, Costco and Staples,” a Google spokesman said.

Although Google has been tiptoeing around the edges of Amazon’s same-day delivery business, its new partnership with Barnes & Noble takes direct aim at loosening Amazon’s firm grip on the online book market. The partnership comes just a day after Amazon announced that it would be expanding its same-day delivery service to six additional cities, including New York, Philadelphia, Dallas and Washington, D.C., bringing the total to 10.

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For Barnes & Noble, Google Shopping represents another opportunity to boost its online sales as the company continues to struggle with its brick and mortar stores. The bookseller's Nook business has also been in steady decline, with Nook revenues falling 35 percent last year and 22 percent just in the last quarter.

But the move also while Amazon is facing its own battles in the book world. The company has been under fire recently over its tactics to extract a better deal for e-book pricing from the publisher Hachette. Customers have complained about sparse availability and long wait times while authors contend that Amazon’s negotiating tactics ultimately prevent more people from reading their work and hurting their bottom line.

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