It is on a blog called 'Modéles pour Bébé au Crochet', however there are a couple of words printed over the image which appear to be in Russian.
There are no written crochet instructions as such on the blog, but the international diagrams are clear and sufficient to make the dress. I assume they have been copied over from a different site...
The blog/website is in French, but is very easy to follow. There are some really pretty other crochet baby patterns on it if you have a search around.
Click here to take you to the crochet pattern diagrams -----> Crochet Baby Dress Pattern
For my Pinterest crochet baby clothes board CLICK HERE - loads of inspiration !