"Janssen" is probably Luplau Janssen, Danish artist

Walldorf, Germany, sells on 22 April 2017 as lot 761 a "Janssen, 19th/20th century" Grieving young woman, a small work (24 by 18 cm) estimated at 550 Euro.

There are many painters named Janssen, but the only one who seems to have had similar subjects, enough artistic merit, and a similar signature, seems to have been Luplau Janssen (1869-1927).

The second signature comes from his portrait of Peter Faber. Most signed works have his full name, and often a date, but considering the small scale of the work for sale, it is not really surprising that he signed with just his surname.

He seems to be situated somewhere in the transition between traditional 19th century genre painting, and more modern, somewhat expressionistic 20th century painting. His subjects (portraits (Kierkegaard shown), sentimental works, some landscapes) are often traditional, but the way he depicts the people is often fairly modern in detail (like his handling of skin and hair).

The estimate for the work for sale seems about right, it is attractive but rather small. His most expensive work I could find fetched nearly 10,000 Euro, but most works are sold for 1,000 Euro or less.