What really effective mosquito repellent? What is there on site?

Hello,

We come to Rwanda for more than 2 months. 2 adults 2 children.

We will not take Malarone for such a long time.

So, which mosquito repellent is really effective? Based on DEET? Icaridine? Eucalyptus citriodora oil?

A brand in particular?

And what can we buy directly in Rwanda? ?

Thank you