Who Are We: Dolls from England and Germany?

The doll on the left, Jetta, is the "Who Am I Doll?"; the Asian doll is by artist, Dwi Saptono.

Jetta, named by her new proud owner, is a black doll from England whose artist is unknown. 

26-inch doll by Lissi Batz has soft vinyl head and arms; rigid plastic body and bent-baby legs, circa 1980s-1990s*

When I saw Jetta's photo, she immediately reminded me of a doll in my collection manufactured in Germany by the Lissi Batz Company, circa 1980s-1990s. 

To aid in Jetta's identification, I asked the owner to share the doll's markings with me, if any.  I also wanted to know Jetta's height and whether or not she is all vinyl.   Betty wrote:

Jetta is 20" tall, has a soft vinyl head and arms and her body and legs are hard plastic.

Jetta is marked on the nape of her neck and under her hairline:

B50/287  or  850/287 

Since I know that dolls by Lissi Batz are marked with the letters LB within a triangle, Betty's doll was probably made by another European manufacturer.

If you are familiar with these markings, with Jetta's mold, or can otherwise help identify the maker of this doll, please share your knowledge in a comment to this post.

Thanks in advance.

*While I know my doll is by Lissi Batz, I do not know her name.  She was purchased on the secondary market during the 1990s.  I dressed her in the infant’s size 3/6 months mint green and light blue checkered romper and white high-top baby shoes that she wears.  If you know her Lissi Batz-given name, I would appreciate the knowledge. 

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