There exists a group of Romanian cinderellas that are often sold as "essays".
These are reproductions of entries to various competitions -
which means that somewhere these has authentic originals
(In much superior quality - compare with this one as example)
- but 99,9% of material for sale is bogus.

The sheets depicted here prove this since:
They consist of designs from a period of 10 years
Definitives depicting Ferdinand and Carol was NOT printed simultaniously.
Definitives and Timbru de ajutor was not printed simultaniously.
Printing quality is substandard and all impressions carry different values.

It is more than probable that more types of sheets than these were printed.