Example of a lattice which has at most 1 complement for its every element but it is not distributive. I know that-

If a lattice is distributive then its every element has either 0 or 1
  complement.

But Is it's converse true?
I am not able to find an example of a lattice which has at most 1 complement for its every element but it is not distributive.
Please give an example. 
 A: A lattice in which each element has at most one complement may have elements with no complement at all.
It is rather easy to come up with non-distributive lattices with that property, even if we require that there is at least one pair of elements which are complements of one another.
For example, take a bounded, non-distributive lattice, in which no element except $0$ and $1$ has a complement.
For a less trivial example, one in which there are other pairs of complements, take the following example:

Here $\langle 0,1\rangle$ and $\langle a,b\rangle$ are the only pairs of complements, and the lattice is not distributive, since it has $M_3$ as a sublattice (see here).
If you're looking for a non-distributive lattice in which every element has a unique complement, that is not easy to point out.
I believe that there is no finite such lattice, but basically this answer tells that it exists (even non-modular).
Actually every lattice is a sublattice of a lattice with unique complements (Dilworth's paper on this).
