diff --git a/rsconcept/frontend/src/models/TMGraph.test.ts b/rsconcept/frontend/src/models/TMGraph.test.ts
new file mode 100644
index 00000000..d6ab181f
--- /dev/null
+++ b/rsconcept/frontend/src/models/TMGraph.test.ts
@@ -0,0 +1,72 @@
+import { TMGraph } from './TMGraph';
+
+const typificationData = [
+  ['', ''],
+  ['X1', 'X1'],
+  ['Z', 'Z'],
+  ['R1', 'R1'],
+  ['C1', 'C1'],
+  ['C1×X1', 'C1 X1 C1×X1'],
+  ['X1×X1', 'X1 X1×X1'],
+  ['X1×X1×X1', 'X1 X1×X1×X1'],
+  ['ℬ(X1)', 'X1 ℬ(X1)'],
+  ['ℬℬ(X1)', 'X1 ℬ(X1) ℬℬ(X1)'],
+  ['ℬℬ(X1×X2)', 'X1 X2 X1×X2 ℬ(X1×X2) ℬℬ(X1×X2)'],
+  ['ℬ((X1×X1)×X2)', 'X1 X1×X1 X2 (X1×X1)×X2 ℬ((X1×X1)×X2)'],
+  ['ℬ(ℬ(X1)×ℬ(X1))', 'X1 ℬ(X1) ℬ(X1)×ℬ(X1) ℬ(ℬ(X1)×ℬ(X1))'],
+  [
+    'ℬ(ℬ((X1×ℬ(X1))×X1)×X2)',
+    'X1 ℬ(X1) X1×ℬ(X1) (X1×ℬ(X1))×X1 ℬ((X1×ℬ(X1))×X1) X2 ℬ((X1×ℬ(X1))×X1)×X2 ℬ(ℬ((X1×ℬ(X1))×X1)×X2)'
+  ]
+];
+describe('Testing parsing typifications', () => {
+  it.each(typificationData)('Typification parsing %p', (input: string, expected: string) => {
+    const graph = new TMGraph();
+    graph.addConstituenta('X1', input, []);
+    const nodeText = graph.nodes.map(node => node.text).join(' ');
+    expect(nodeText).toBe(expected);
+  });
+});
+
+describe('Testing constituents parsing', () => {
+  test('simple expression no arguments', () => {
+    const graph = new TMGraph();
+    graph.addConstituenta('X1', 'ℬ(X1)', []);
+
+    expect(graph.nodes.length).toBe(2);
+    expect(graph.nodes.at(-1)?.annotations).toStrictEqual(['X1']);
+  });
+
+  test('no expression with single argument', () => {
+    const graph = new TMGraph();
+    graph.addConstituenta('X1', '', [{ alias: 'a', typification: 'X1' }]);
+    const nodeText = graph.nodes.map(node => node.text).join(' ');
+
+    expect(nodeText).toBe('X1 ℬ(X1)');
+    expect(graph.nodes.at(-1)?.annotations).toStrictEqual(['X1']);
+  });
+
+  test('no expression with multiple arguments', () => {
+    const graph = new TMGraph();
+    graph.addConstituenta('X1', '', [
+      { alias: 'a', typification: 'X1' },
+      { alias: 'b', typification: 'R1×X1' }
+    ]);
+    const nodeText = graph.nodes.map(node => node.text).join(' ');
+
+    expect(nodeText).toBe('X1 R1 R1×X1 X1×(R1×X1) ℬ(X1×(R1×X1))');
+    expect(graph.nodes.at(-1)?.annotations).toStrictEqual(['X1']);
+  });
+
+  test('expression with multiple arguments', () => {
+    const graph = new TMGraph();
+    graph.addConstituenta('X1', 'ℬ(X2×Z)', [
+      { alias: 'a', typification: 'X1' },
+      { alias: 'b', typification: 'R1×X1' }
+    ]);
+    const nodeText = graph.nodes.map(node => node.text).join(' ');
+
+    expect(nodeText).toBe('X1 R1 R1×X1 X1×(R1×X1) X2 Z X2×Z ℬ(X2×Z) (X1×(R1×X1))×ℬ(X2×Z) ℬ((X1×(R1×X1))×ℬ(X2×Z))');
+    expect(graph.nodes.at(-1)?.annotations).toStrictEqual(['X1']);
+  });
+});
diff --git a/rsconcept/frontend/src/models/TMGraph.ts b/rsconcept/frontend/src/models/TMGraph.ts
new file mode 100644
index 00000000..b14a1265
--- /dev/null
+++ b/rsconcept/frontend/src/models/TMGraph.ts
@@ -0,0 +1,213 @@
+/**
+ * Module: Multi-graph for typifications.
+ */
+
+import { IArgumentInfo } from './rslang';
+
+/**
+ * Represents a single node of a {@link TMGraph}.
+ */
+export interface TMGraphNode {
+  id: number;
+  rank: number;
+  text: string;
+  parents: number[];
+  annotations: string[];
+}
+
+/**
+ * Represents a typification multi-graph.
+ */
+export class TMGraph {
+  /** List of nodes. */
+  nodes: TMGraphNode[] = [];
+  /** Map of nodes by ID. */
+  nodeById = new Map<number, TMGraphNode>();
+  /** Map of nodes by alias. */
+  nodeByAlias = new Map<string, TMGraphNode>();
+
+  /**
+   * Adds a constituent to the graph.
+   *
+   * @param alias - The alias of the constituent.
+   * @param result - typification of the formal definition.
+   * @param args - arguments for term or predicate function.
+   */
+  addConstituenta(alias: string, result: string, args: IArgumentInfo[]): void {
+    const argsNode = this.processArguments(args);
+    const resultNode = this.processResult(result);
+    const combinedNode = this.combineResults(resultNode, argsNode);
+    if (!combinedNode) {
+      return;
+    }
+    this.addAliasAnnotation(combinedNode.id, alias);
+  }
+
+  addBaseNode(baseAlias: string): TMGraphNode {
+    const existingNode = this.nodes.find(node => node.text === baseAlias);
+    if (existingNode) {
+      return existingNode;
+    }
+
+    const node: TMGraphNode = {
+      id: this.nodes.length,
+      text: baseAlias,
+      rank: 0,
+      parents: [],
+      annotations: []
+    };
+    this.nodes.push(node);
+    this.nodeById.set(node.id, node);
+    return node;
+  }
+
+  addBooleanNode(parent: number): TMGraphNode {
+    const existingNode = this.nodes.find(node => node.parents.length === 1 && node.parents[0] === parent);
+    if (existingNode) {
+      return existingNode;
+    }
+
+    const parentNode = this.nodeById.get(parent);
+    if (!parentNode) {
+      throw new Error(`Parent node ${parent} not found`);
+    }
+
+    const text = parentNode.parents.length === 1 ? `ℬ${parentNode.text}` : `ℬ(${parentNode.text})`;
+    const node: TMGraphNode = {
+      id: this.nodes.length,
+      rank: parentNode.rank,
+      text: text,
+      parents: [parent],
+      annotations: []
+    };
+    this.nodes.push(node);
+    this.nodeById.set(node.id, node);
+    return node;
+  }
+
+  addCartesianNode(parents: number[]): TMGraphNode {
+    const existingNode = this.nodes.find(
+      node => node.parents.length === parents.length && node.parents.every((p, i) => p === parents[i])
+    );
+    if (existingNode) {
+      return existingNode;
+    }
+
+    const parentNodes = parents.map(parent => this.nodeById.get(parent));
+    if (parentNodes.some(parent => !parent) || parents.length < 2) {
+      throw new Error(`Parent nodes ${parents.join(', ')} not found`);
+    }
+
+    const text = parentNodes.map(node => (node!.parents.length > 1 ? `(${node!.text})` : node!.text)).join('×');
+    const node: TMGraphNode = {
+      id: this.nodes.length,
+      text: text,
+      rank: Math.max(...parentNodes.map(parent => parent!.rank)) + 1,
+      parents: parents,
+      annotations: []
+    };
+    this.nodes.push(node);
+    this.nodeById.set(node.id, node);
+    return node;
+  }
+
+  addAliasAnnotation(node: number, alias: string): void {
+    const nodeToAnnotate = this.nodeById.get(node);
+    if (!nodeToAnnotate) {
+      throw new Error(`Node ${node} not found`);
+    }
+    nodeToAnnotate.annotations.push(alias);
+    this.nodeByAlias.set(alias, nodeToAnnotate);
+  }
+
+  private processArguments(args: IArgumentInfo[]): TMGraphNode | undefined {
+    if (args.length === 0) {
+      return undefined;
+    }
+    const argsNodes = args.map(argument => this.parseToNode(argument.typification));
+    if (args.length === 1) {
+      return argsNodes[0];
+    }
+    return this.addCartesianNode(argsNodes.map(node => node.id));
+  }
+
+  private processResult(result: string): TMGraphNode | undefined {
+    if (!result) {
+      return undefined;
+    }
+    return this.parseToNode(result);
+  }
+
+  private combineResults(result: TMGraphNode | undefined, args: TMGraphNode | undefined): TMGraphNode | undefined {
+    if (!result && !args) {
+      return undefined;
+    }
+    if (!result) {
+      return this.addBooleanNode(args!.id);
+    }
+    if (!args) {
+      return result;
+    }
+    const argsAndResult = this.addCartesianNode([args.id, result.id]);
+    return this.addBooleanNode(argsAndResult.id);
+  }
+
+  private parseToNode(typification: string): TMGraphNode {
+    const tokens = this.tokenize(typification);
+    return this.parseTokens(tokens);
+  }
+
+  private tokenize(expression: string): string[] {
+    const tokens = [];
+    let currentToken = '';
+    for (const char of expression) {
+      if (['(', ')', '×', 'ℬ'].includes(char)) {
+        if (currentToken) {
+          tokens.push(currentToken);
+          currentToken = '';
+        }
+        tokens.push(char);
+      } else {
+        currentToken += char;
+      }
+    }
+    if (currentToken) {
+      tokens.push(currentToken);
+    }
+    return tokens;
+  }
+
+  private parseTokens(tokens: string[], isBoolean: boolean = false): TMGraphNode {
+    const stack: TMGraphNode[] = [];
+    let isCartesian = false;
+    while (tokens.length > 0) {
+      const token = tokens.shift();
+      if (!token) {
+        throw new Error('Unexpected end of expression');
+      }
+
+      if (isBoolean && token === '(') {
+        return this.parseTokens(tokens);
+      }
+
+      if (token === ')') {
+        break;
+      } else if (token === 'ℬ') {
+        const innerNode = this.parseTokens(tokens, true);
+        stack.push(this.addBooleanNode(innerNode.id));
+      } else if (token === '×') {
+        isCartesian = true;
+      } else if (token === '(') {
+        stack.push(this.parseTokens(tokens));
+      } else {
+        stack.push(this.addBaseNode(token));
+      }
+    }
+
+    if (isCartesian) {
+      return this.addCartesianNode(stack.map(node => node.id));
+    } else {
+      return stack.pop()!;
+    }
+  }
+}