Coreopsis Seeds- To cover or not to cover

I am getting conflicting information on how to treat coreopsis seeds. The seed packet from Stokes says to cover the seeds with fine soil. A website on how to grow coreopsis says to press the seeds into the soil and not cover them at all as they need light to germinate. So who's correct?

I would follow Stokes advise. They are one of the best seed companies out there. BTW what species/variety are you growing? Conditions needed will vary by species/variety/

Coreopsis seeds need to be covered very thin: 1/15th inch. They need some light to germinate, but they need a good contact with the soil.

I'm growing Coreopsis grandiflora var. Sunray. To cover my bases I covered part of the planting thinly and simply pressed the remainder of the seeds into the soil, lightly sprayed them, and then covered the pots with a piece of scrap glass to keep them from drying out. I sat the pots on a northeast facing windowsill and today after only 4 days, I already have seedlings! Stokes said to expect germination in about 20 days. A planting of Shasta daisy left uncovered and treated the same way is also germinating, again much earlier than expected. Thanks to Jonna and trc65 for your prompt replies. I love this website!