The Official Grumpy Cat

Look out, Grumpy Cat: Garfi 'angry cat' photos go viral

How to Calm an Angry Cat

Resting cat face (RCF). - Modkat

Illustration Three Angry Cats

Grumpy Cat RIP: A look back at the life of famous cat - BBC Newsround

New Grumpy Cat' has permanently sad face due to rare medical condition

Angry Kitty, We Bare Bears Wiki

RIP Grumpy Cat: Looking back on her best memes, Article

How Grumpy Cat went from feline obscurity to internet sensation

Report that Grumpy Cat made $99.5 million in two years is completely inaccurate - Vox